NTSC/PAL Digital Video Encoder

CS4954
CS4955
NTSC/PAL Digital Video Encoder
Features
Description
Six DACs providing simultaneous composite,
The CS4954/5 provides full conversion from digital video
formats YCbCr or YUV into NTSC and PAL Composite,
Y/C (S-video) and RGB, or YUV analog video. Input formats can be 27 MHz 8-bit YUV, 8-bit YCbCr, or ITU
R.BT656 with support for EAV/SAV codes. Video output
can be formatted to be compatible with NTSC-M, NTSCJ, PAL-B,D,G,H,I,M,N, and Combination N systems.
Closed Caption is supported in NTSC. Teletext is supported for NTSC and PAL.
S-video, and RGB or Component YUV
outputs
Programmable DAC output currents for low
impedance (37.5 Ω) and high impedance
(150 Ω) loads.
Multi-standard support for NTSC-M, NTSCJAPAN, PAL (B, D, G, H, I, M, N,
Combination N)
Six 10-bit DACs provide two channels for an S-Video
output port, one or two composite video outputs, and
ITU R.BT656 input mode supporting
EAV/SAV codes and CCIR601 Master/Slave three RGB or YUV outputs. Two-times oversampling reduces the output filter requirements and guarantees no
input modes
DAC-related modulation components within the speci Programmable HSYNC and VSYNC timing fied bandwidth of any of the supported video standards.
Multistandard Teletext (Europe, NABTS,
Parallel or high-speed I2C compatible control interfaces are
WST) support
provided for flexibility in system design. The parallel interface
VBI encoding support
doubles as a general purpose I/O port when the CS4954/5 is
Wide-Screen Signaling (WSS) support, EIA-J in I2C mode to help conserve valuable board area.
CPX1204
ORDERING INFORMATION
NTSC closed caption encoder with interrupt
CS4954-CQ
48-pin TQFP
CS4955-CQ
48-pin TQFP
CS4955 supports Macrovision copy
protection Version 7
Host interface configurable
VAA
for parallel or I2C
CLK
Output
LPF
10-Bit
SCL
I2C Interface
C
Interpolate
DAC
SDA
compatible operation
8
Control
10-Bit
Chroma Amplifier Σ
On-chip voltage reference
PDAT[7:0]
CVBS
Registers
DAC
Host
RD
Parallel
generator
Chroma Modulate
WR
10-Bit
Interface
Y
DAC
PADR
+3.3 V or +5 V operation,
Burst Insert
XTAL_IN
10-Bit
Color Sub-carrier Synthesizer
CMOS, low-power modes,
R
XTAL_OUT
DAC
Chroma Interpolate
tri-state DACs
10-Bit
Teletext
Encoder
TTXDAT
TTXRQ
YCbCr to RBG
Color Space
Converter
U,V
LPF
8
VD[7:0]
HSYNC
VSYNC
FIELD
INT
RESET
Video Formatter
DAC
G
10-Bit
DAC
B
Y Luma Interpolate
Voltage
Reference
Video Timing
Generator
Luma Amplifier
Current
Y
Y
Reference
Sync Insert
RGB
RGB
DGND
Copyright  Cirrus Logic, Inc. 2003
(All Rights Reserved)
www.cirrus.com
VREF
ISET
TEST
September 2003
DS278F1
1
CS4954 CS4955
Contacting Cirrus Logic Support
For all product questions and inquiries contact a Cirrus Logic Sales Representative.
To find the one nearest to you go to www.cirrus.com
IMPORTANT NOTICE
Cirrus Logic, Inc. and its subsidiaries ("Cirrus") believe that the information contained in this document is accurate and relia ble. However, the information is subject
to change without notice and is provided "AS IS" without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. No responsibility is assumed by
Cirrus for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights
of third parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work
rights, copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and
gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This
consent does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
An export permit needs to be obtained from the competent authorities of the Japanese Government if any of the products or techno logies described in this material
and controlled under the "Foreign Exchange and Foreign Trade Law" is to be exported or taken out of Japan. An export license and/or quota needs to be obtained
from the competent authorities of the Chinese Government if any of the products or technologies described in this material is su bject to the PRC Foreign Trade Law
and is to be exported or taken out of the PRC.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE
IN AIRCRAFT SYSTEMS, MILITARY APPLICATIONS, PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS (INCLUDING MEDICAL DEVICES, AIRCRAFT SYSTEMS OR COMPONENTS AND PERSONAL OR AUTOMOTIVE SAFETY OR SECURITY DEVICES). INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER’S RISK AND CIRRUS
DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR PARTICULAR PURPOSE, WITH REGARD TO ANY CIRRUS PRODUCT THAT IS USED IN SUCH A MANNER. IF THE CUSTOMER OR CUSTOMER’S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES, BY SUCH USE, TO
FULLY INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER AGENTS FROM ANY AND ALL LIABILITY, INCLUDING ATTORNEYS’ FEES AND COSTS, THAT MAY RESULT FROM OR ARISE IN CONNECTION WITH THESE USES.
Cirrus Logic, Cirrus, the Cirrus Logic logo designs, and Crystal are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be
trademarks or service marks of their respective owners.
I2C is a registered trademark of Philips Semiconductor. Purchase of I2C Components of Cirrus Logic, Inc., or one of its sublicensed Associated Companies conveys
a license under the Philips I2C Patent Rights to use those components in a standard I2C system.
Macrovision is a trademark of Macrovision Corporation. It is hereby notified that a third-party license from Macrovision Corpor ation is necessary to distribute software of Macrovision Corporation in any finished end-user or ready-to-use final product.
2
DS278F1
CS4954 CS4955
TABLE OF CONTENTS
1.
2.
3.
4.
5.
6.
7.
DS278F1
CHARACTERISTICS AND SPECIFICATIONS .................................................................. 6
AC & DC PARAMETRIC SPECIFICATIONS ...................................................................... 6
RECOMMENDED OPERATING CONDITIONS ..................................................................... 6
DC CHARACTERISTICS .................................................................................................... 6
AC CHARACTERISTIC ...................................................................................................... 8
TIMING CHARACTERISTICS ............................................................................................. 9
ADDITIONAL CS4954/5 FEATURES ............................................................................... 11
CS4954 INTRODUCTION ................................................................................................ 11
FUNCTIONAL DESCRIPTION ......................................................................................... 11
4.1
Video Timing Generator ......................................................................................... 11
4.2
Video Input Formatter ............................................................................................ 12
4.3
Color Subcarrier Synthesizer ................................................................................. 12
4.4
Chroma Path .......................................................................................................... 12
4.5
Luma Path .............................................................................................................. 13
4.6
RGB Path and Component YUV Path .................................................................... 13
4.7
Digital to Analog Converters .................................................................................. 13
4.8
Voltage Reference ................................................................................................. 14
4.9
Current Reference .................................................................................................. 14
4.10 Host Interface ......................................................................................................... 14
4.11 Closed Caption Services ........................................................................................ 14
4.12 Teletext Services .................................................................................................... 15
4.13 Wide-Screen Signaling Support and CGMS .......................................................... 15
4.14 VBI Encoding ......................................................................................................... 15
4.15 Control Registers ................................................................................................... 15
4.16 Testability ............................................................................................................... 15
OPERATIONAL DESCRIPTION ...................................................................................... 15
5.1
Reset Hierarchy ..................................................................................................... 15
5.2
Video Timing .......................................................................................................... 16
5.2.1 Slave Mode Input Interface ......................................................................... 16
5.2.2 Master Mode Input Interface ....................................................................... 16
5.2.3 Vertical Timing ............................................................................................. 17
5.2.4 Horizontal Timing ........................................................................................ 17
5.2.5 NTSC Interlaced .......................................................................................... 17
5.2.6 PAL Interlaced ............................................................................................. 17
5.2.7 Progressive Scan ........................................................................................ 18
5.2.8 NTSC Progressive Scan ............................................................................. 18
5.2.9 PAL Progressive Scan ................................................................................ 19
5.3
ITU-R.BT656 .......................................................................................................... 19
5.4
Digital Video Input Modes ...................................................................................... 22
5.5
Multi-standard Output Format Modes .................................................................... 22
5.6
Subcarrier Generation ............................................................................................ 22
5.7
Subcarrier Compensation ...................................................................................... 22
5.8
Closed Caption Insertion ........................................................................................ 23
5.9
Programmable H-sync and V-sync ........................................................................ 23
5.10 Wide Screen Signaling (WSS) and CGMS ............................................................ 24
5.11 Teletext Support ..................................................................................................... 24
5.12 Color Bar Generator ............................................................................................... 26
5.13 VBI encoding .......................................................................................................... 26
5.14 Super White/Super Black support .......................................................................... 27
5.15 Interrupts ................................................................................................................ 27
5.16 General Purpose I/O Port ....................................................................................... 27
FILTER RESPONSES ...................................................................................................... 28
ANALOG .......................................................................................................................... 31
7.1
Analog Timing ........................................................................................................ 31
7.2
VREF ...................................................................................................................... 31
7.3
ISET ....................................................................................................................... 31
7.4
DACs ...................................................................................................................... 31
7.4.1 Luminance DAC .......................................................................................... 31
7.4.2 Chrominance DAC ...................................................................................... 31
7.4.3 CVBS DAC .................................................................................................. 32
7.4.4 Red DAC ..................................................................................................... 32
3
CS4954 CS4955
7.4.5 Green DAC ..................................................................................................32
7.4.6 Blue DAC .....................................................................................................32
8. PROGRAMMING ..............................................................................................................33
8.1
Host Control Interface .............................................................................................33
8.1.1 I2C Interface .................................................................................................33
8.1.2 8-bit Parallel Interface ..................................................................................34
8.2
Register Description ...............................................................................................35
8.2.1 Control Registers .........................................................................................35
9. BOARD DESIGN AND LAYOUT CONSIDERATIONS ....................................................51
9.1
Power and Ground Planes .....................................................................................51
9.2
Power Supply Decoupling ......................................................................................51
9.3
Digital Interconnect .................................................................................................51
9.4
Analog Interconnect ................................................................................................51
9.5
Analog Output Protection .......................................................................................52
9.6
ESD Protection .......................................................................................................52
9.7
External DAC Output Filter .....................................................................................52
10. PIN DESCRIPTION ..........................................................................................................54
11. PACKAGE DRAWING ......................................................................................................56
12.
4
DS278F1
CS4954 CS4955
LIST OF FIGURES
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
Figure 20.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
Figure 30.
Figure 31.
5
Video Pixel Data and Control Port Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
I2C Host Port Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
ITU R.BT601 Input Slave Mode Horizontal Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
ITU R.BT601 Input Master Mode Horizontal Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Vertical Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
NTSC Video Interlaced Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
PAL Video Interlaced Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
NTSC Video Non-Interlaced Progressive Scan Timing . . . . . . . . . . . . . . . . . . . . . . . . 21
PAL Video Non-Interlaced Progressive Scan Timing . . . . . . . . . . . . . . . . . . . . . . . . . 21
CCIR656 Input Mode Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Teletext Timing (Pulsation Mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Teletext Timing (Window Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
1.3 Mhz Chrominance low-pass filter transfer characteristic . . . . . . . . . . . . . . . . . . . 28
1.3 Mhz Chrominance low-pass filter transfer characterstic (passband) . . . . . . . . . . 28
650 kHz Chrominance low-pass filter transfer characteristic . . . . . . . . . . . . . . . . . . . 28
650 kHz Chrominance low-pass filter transfer characteristic (passband). . . . . . . . . . 28
Chrominance output interpolation filter transfer characteristic (passband). . . . . . . . . 29
Luminance interpolation filter transfer characteristic . . . . . . . . . . . . . . . . . . . . . . . . . 29
Luminance interpolation filter transfer characterstic (passband) . . . . . . . . . . . . . . . . 29
Chrominance interpolation filter transfer characteristic for RGB datapath . . . . . . . . . 29
Chroma Interpolator for RGB Datapath when rgb_bw=1 (Reduced Bandwidth) . . . .30
Chroma Interpolator for RGB Datapath when rgb_bw=1 (Reduced Bandwidth) . . . .30
Chroma Interpolator for RGB Datapath when rgb_bw=0 - 3dB . . . . . . . . . . . . . . . . . 30
Chroma Interpolator for RGB Datapath when rgb_bw=0 (Full Scale). . . . . . . . . . . . . 30
I2C Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
8-bit Parallel Host Port Timing: Read-Write/Write-Read Cycle. . . . . . . . . . . . . . . . . . 34
8-bit Parallel Host Port Timing: Address Read Cycle . . . . . . . . . . . . . . . . . . . . . . . . . 34
8-bit Parallel Host Port Timing: Address Write Cycle . . . . . . . . . . . . . . . . . . . . . . . . . 35
External Low Pass Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Typical Connection Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
DS278F1
CS4954 CS4955
1. CHARACTERISTICS AND SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
AC & DC PARAMETRIC SPECIFICATIONS (AGND,DGND = 0 V, all voltages with respect to 0 V )
Parameter
Power Supply
Symbol
Min
Max
VAA/VDD
Units
-0.3
6.0
V
Input Current Per Pin (Except Supply Pins)
-10
10
mA
Output Current Per Pin (Except Supply Pins)
-50
+50
mA
Analog Input Voltage
-0.3
VAA + 0.3
V
Digital Input Voltage
-0.3
VDD + 0.3
V
Ambient Temperature Power Applied
-55
+ 125
°C
Storage Temperature
-65
+ 150
°C
WARNING: Operating beyond these limits can result in permanent damage to the device. Normal operation is not
guaranteed at these extremes.
RECOMMENDED OPERATING CONDITIONS (AGND,DGND = 0 V, all voltages with respect to 0 V.)
Parameter
Symbol
Min
Typ
Max
Units
Power Supplies: Digital Analog
VAA/VDD
3.15
4.75
3.3
5.0
3.45
5.25
V
Operating Ambient Temperature
TA
0
+ 25
+ 70
°C
Note:
Operation outside the ranges is not recommended.
DC CHARACTERISTICS
(TA = 25° C; VAA, VDD = 5 V; GNDA, GNDD = 0 V.)
Parameter
Symbol
Min
Typ
Max
Units
High level Input Voltage
V [7:0], PDAT [7:0], Hsync/Vsync/Field/CLKIN
VIH
2.2
-
VDD+0.3
V
High Level Input Voltage I2C
VIH
0.7 VDD
-
-
V
Low level Input Voltage All Inputs
-
-0.3
-
0.8
V
Input Leakage Current
-
-10
-
+10
µA
High Level Output Voltage lo = -4 mA
VOH
2.4
-
VDD
V
Low level Output Voltage lo = 4 mA
VOL
-
-
0.4
V
Low Level Output Voltage SDA pin only, lo = 6mA
VOL
-
-
0.4
V
-
-10
-
+ 10
µA
Digital Inputs
Digital Outputs
Output Leakage Current High-Z Digital Outputs
6
DS278F1
CS4954 CS4955
DC CHARACTERISTICS
(Continued)
Parameter
Symbol
Min
Typ
Max
Units
Analog Outputs
Full Scale Output Current CVBS/Y/C/R/G/B
(Notes 1, 2, 3)
IO
32.9
34.7
36.5
mA
Full Scale Output Current CVBS/Y/C/R/G/B
(Notes 1, 2, 4)
IO
8.22
8.68
9.13
mA
LSB Current CVBS/Y/C/R/G/B
(Notes 1, 2, 3)
IB
32.2
33.9
35.7
µA
LSB Current CVBS/Y/C/R/G/B
(Notes 1, 2, 4)
IB
8.04
8.48
8.92
µA
DAC-to-DAC Matching
(Note 1)
MAT
-
2
4
%
Output Compliance
(Note 1)
VOC
0
-
+ 1.4
V
Output Impedance
(Note 1)
ROUT
-
15
-
kΩ
Output Capacitance
(Note 1)
COUT
-
-
30
pF
DAC Output Delay
(Note 1)
ODEL
-
4
12
ns
TRF
-
2.5
5
ns
VOV
1.170
1.232
1.294
V
UVC
-
-
10
uA
VAA, VDD
3.15
4.75
3.3
5.0
3.45
5.25
V
DAC Rise/Fall Time
(Note 1, 5)
Voltage Reference
Reference Voltage Output
Reference Input Current
(Note 1)
Power Supply
Supply Voltage
Digital Supply Current
IAA1
-
70
150
mA
Analog Supply
Low-Z
(Note 6)
IAA2
-
100
150
mA
Analog Supply
High-Z
(Note 7)
IAA3
-
60
100
mA
0.02
0.05
V/V
-
-
10
Bits
Power Supply Rejection Ratio
PSRR
Static Performance
DAC Resolution
(Note 1)
Differential Non-Linearity
(Note 1)
DNL
-1
+ 0.5
+1
LSB
Integral Non-Linearity
(Note 1)
INL
-2
+1
+2
LSB
Differential Gain
(Note 1)
DG
-
2
5
%
Differential Phase
(Note 1)
DP
-
+ 0. 5
+2
°
Hue Accuracy
(Note 1)
HA
-
-
2
°
SNR
70
-
-
dB
SAT
-
1
2
%
Dynamic Performance
Signal to Noise Ratio
Saturation Accuracy
(Note 1)
Notes: 1. Values are by characterization only
2. Output current levels with ISET = 4K Ω , VREF = 1.232 V.
3. DACs are set to low impedance mode
4. DACs are set to high impedance mode
5. Times for black-to-white-level and white-to-black-level transitions.
6. Low-Z, 3 dacs on
7. High-Z, 6 dacs on
DS278F1
7
CS4954 CS4955
AC CHARACTERISTIC
Parameter
Pixel Input and Control Port (Figure 1)
Clock Pulse High Time
Clock Pulse Low Time
Symbol
Min
Typ
Max
Units
Tch
14.82
18.52
22.58
ns
Tcl
14.82
18.52
22.58
ns
Clock to Data Set-up Time
Tisu
6
-
-
ns
Clock to Data Hold Time
Tih
0
-
-
ns
Clock to Data Output Delay
Toa
-
-
17
ns
CLK
Tisu
Tch
Tcl
V[7:0]
Tih
HSYNC/VSYNC
(Inputs)
Toa
HSYNC/VSYNC
CB/FIELD/INT
(Outputs)
Figure 1. Video Pixel Data and Control Port Timing
8
DS278F1
CS4954 CS4955
TIMING CHARACTERISTICS
Parameter
Symbol
Min
I C Host Port Timing (Figure 2)
SCL Frequency
Fclk
100
Typ
Max
Units
1000
KHz
2
Clock Pulse High Time
Tsph
0.1
µs
Clock Pulse Low Time
Tspl
0.7
µs
Hold Time (Start Cond.)
Tsh
100
ns
Setup Time (Start Cond.)
Tssu
100
ns
Data Setup Time
Tsds
50
ns
Rise Time
Tsr
1
µs
Fall Time
Tsf
0.3
µs
Setup Time (Stop Cond.)
Tss
100
Bus Free Time
Tbuf
100
ns
Data Hold Time
Tdh
0
ns
SCL Low to Data Out Valid
Tvdo
ns
600
ns
Tds
Tsh
Tbu
Tsh
Tdh
Tss
SDA
Tsr
Tsph
Tvdo
SCL
Tspi
Tsi
Tssu
Figure 2. I2C Host Port Timing
DS278F1
9
CS4954 CS4955
TIMING CHARACTERISTICS(Continued)
Parallel Host Port Timing (Figure 27, 28, 29)
Symbol
Min
Typ
Max
Units
Read Cycle Time
Trd
60
-
-
ns
Read Pulse Width
Trpw
30
-
-
ns
Address Setup Time
Tas
3
-
-
ns
Read Address Hold Time
Trah
10
-
-
ns
Read Data Access Time
Trda
-
-
40
ns
Read Data Hold Time
Trdh
10
-
50
ns
Write Recovery Time
Twr
60
-
-
ns
Twpw
40
-
-
ns
Write Pulse Width
Write Data Setup Time
Twds
8
-
-
ns
Write Data Hold Time
Twdh
3
-
-
ns
Write-Read/Read-Write Recovery Time
Trec
50
-
-
ns
Address from Write Hold Time
Twac
0
-
-
ns
Tres
100
Reset Timing (Figure 3)
Reset Pulse Width
ns
RESET*
Tres
Figure 3. Reset Timing
10
DS278F1
CS4954 CS4955
2.
ADDITIONAL CS4954/5 FEATURES
•
Five programmable DAC output combinations,
including YUV and second composite
•
Optional progressive scan @ MPEG2 field rates
•
Stable color subcarrier for MPEG2 systems
•
General purpose input and output pins
•
Individual DAC power-down capability
•
On-chip color bar generator
•
Supports RS170A and ITU R.BT601 composite output timing
•
HSYNC and VSYNC output in ITU R.BT656
mode
•
Teletext encoding selectable on two composite
and S-video signals
•
Programmable saturation, SCH Phase, hue,
brightness and contrast
•
Device power-down capability
•
Super White and Super Black support
3.
CS4954 INTRODUCTION
The CS4954/5 is a complete multi-standard digital
video encoder implemented in current CMOS technology. The device can operate at 5V as well as at
3.3 V. ITU R.BT601- or ITU R.BT656-compliant
digital video input is converted into NTSC-M,
NTSC-J, PAL-B, PAL-D, PAL-G, PAL-H, PAL-I,
PAL-M, PAL-N, or PAL-N Argentina-compatible
analog video. The CS4954/5 is designed to connect, without glue logic, to MPEG1 and MPEG2
digital video decoders.
Two 10-bit DAC outputs provide high quality SVideo analog output while another 10-bit DAC simultaneously generates composite analog video. In
addition, there are three more DACs to provide simultaneous analog RGB or analog YUV outputs.
The CS4954/5 will accept 8-bit YCbCr or 8-bit
YUV input data.
DS278F1
The CS4954/5 is completely configured and controlled via an 8-bit host interface port or an I2C
compatible serial interface. This host port provides
access and control of all CS4954/5 options and features, such as closed caption insertion, interrupts,
etc.
In order to lower overall system costs, the
CS4954/5 provides an internal voltage reference
that eliminates the requirement for an external, discrete, three-pin voltage reference.
In ISO MPEG-2 system configurations, the
CS4954/5 can be augmented with a common colorburst crystal to provide a stable color subcarrier
given an unstable 27 MHz clock input. The use of
the crystal is optional, but the facility to connect
one is provided for MPEG-2 environments in
which the system clock frequency variability is too
wide for accurate color sub-carrier generation.
4.
FUNCTIONAL DESCRIPTION
In the following subsections, the functions of the
CS4954/5 will be described. The descriptions refer
to the device elements shown in the block diagram
on the cover page.
4.1
Video Timing Generator
All timing generation is accomplished via a
27 MHz input applied to the CLK pin. The
CS4954/5 can also accept a signal from an optional
color burst crystal on the XTAL_IN &
XTAL_OUT pins. See the section, Color Subcarrier Synthesizer, for further details.
The Video Timing Generator is responsible for orchestrating most of the other modules in the device.
It operates in harmony with external sync input
timing, or it can provide external sync timing outputs. It automatically disables color burst on appropriate scan lines and automatically generates
serration and equalization pulses on appropriate
scan lines.
11
CS4954 CS4955
The CS4954/5 is designed to function as a video
timing master or video timing slave. In both Master
and Slave Modes, all timing is sampled and asserted with the rising edge of the CLK pin.
CLK input (27 MHz). Color burst accuracy and
stability are limited by the accuracy of the 27MHz
input. If the frequency varies, then the color burst
frequency will also vary accordingly.
In most cases, the CS4954/5 will serve as the video
timing master. HSYNC, VSYNC, and FIELD are
configured as outputs in Master Mode. HSYNC or
FIELD can also be defined as a composite blanking
output signal in Master Mode. In Master Mode, the
timing of HSYNC, VSYNC, FIELD and Composite Blank (CB) signals is programmable. Exact horizontal and vertical display timing is addressed in
the Operational Description section.
For environments in which the CLK input varies or
jitters unacceptably, a local crystal frequency reference can be used on the XTAL_IN and
XTAL_OUT pins. In this instance, the input CLK is
continuously compared with the external crystal reference input and the internal timing of the CS4954/5
is automatically adjusted so that the color burst frequency remains within tolerance.
In Slave Mode, HSYNC and VSYNC are typically
configured as input pins and are used to initialize
independent vertical and horizontal timing generators upon their respective falling edges. HSYNC
and VSYNC timing must conform to the ITUR BT.601 specifications.
The CS4954/5 also provides a ITU R.BT656 Slave
Mode in which the video input stream contains
EAV and SAV codes. In this case, proper HSYNC
and VSYNC timing are extracted automatically
without any inputs other than the V [7:0]. ITU
R.BT656 input data is sampled with the leading
edge of CLK.
In addition, it is also possible to output HSYNC
and VSYNC signals during CCIR-656 Slave
Mode.
4.2
Video Input Formatter
The Video Input Formatter translates YCbCr input
data into YUV information, when necessary, and
splits the luma and chroma information for filtering, scaling, and modulation.
4.3
Color Subcarrier Synthesizer
The subcarrier synthesizer is a digital frequency
synthesizer that produces the appropriate subcarrier frequency for NTSC or PAL. The CS4954/5
generates the color burst frequency based on the
12
Controls are provided for phase adjustment of the
burst to permit color adjustment and phase compensation. Chroma hue control is provided by the
CS4954/5 via a 10-bit Hue Control Register
(HUE_LSB and H_MSB). Burst amplitude control
is also made available to the host via the 8-bit burst
amplitude register (SC_AMP).
4.4
Chroma Path
The Video Input Formatter delivers 4:2:2 YUV
outputs into separate chroma and luma data paths.
The chroma path will be discussed here.
The chroma output of the Video Input Formatter is
directed to a chroma low-pass 19-tap FIR filter.
The filter bandwidth is selected (or the filter can be
bypassed) via the CONTROL_1 Register. The
passband of the filter is either 650 KHz or 1.3 MHz
and the passband ripple is less than or equal to
0.05 dB. The stopband for the 1.3 MHz selection
begins at 3 MHz with an attenuation of greater than
35 dB. The stopband for the 650 KHz selection begins around 1.1 MHz with an attenuation of greater
than 20dB.
The output of the chroma low-pass filter is connected to the chroma interpolation filter in which upsampling from 4:2:2 to 4:4:4 is accomplished.
Following the interpolation filter, the U and V
chroma signals pass through two independent variable gain amplifiers in which the chroma amplitude
DS278F1
CS4954 CS4955
can be varied via the U_AMP and V_AMP 8-bit
host addressable registers.
The U and V chroma signals are fed to a quadrature
modulator in which they are combined with the
output from the subcarrier synthesizer to produce
the proper modulated chrominance signal.
The chroma then is interpolated by a factor of two
in order to operate the output DACs at twice the
pixel rate. The interpolated filters enable running
the DACs at twice the pixel rate and this helps reduce the sinx/x roll-off for higher frequencies and
reduces the complexity of the external analog low
pass filters.
4.5
Luma Path
Along with the chroma output path, the CS4954/5
Video Input Formatter initiates a parallel luma data
path by directing the luma data to a digital delay
line. The delay line is built as a digital FIFO in
which the depth of the FIFO replicates the clock
period delay associated with the more complex
chroma path. Brightness adjustment is also provided via the 8-bit BRIGHTNESS_OFFSET Register.
Following the luma delay, the data is passed
through an interpolation filter that has a programmable bandwidth, followed by a variable gain amplifier in which the luma DC values are modifiable
via the Y_AMP Register.
three pixel clocks. This variable delay is useful to
offset different propagation delays of the luma
baseband and modulated chroma signals. This adjustable luma delay is available only on the
CVBS_1 output.
4.6
RGB Path and Component YUV Path
The RGB datapath has the same latency as the luma
and chroma path. Therefore all six simultaneous
analog outputs are synchronized. The 4:2:2 YCbCr
data is first interpolated to 4:4:4 and then interpolated to 27 MHz. The color space conversion is performed at 27 MHz. The coefficients for the color
space conversion conform to the ITU R.BT601
specifications.
After color space conversion, the amplitude of each
component can be independently adjusted via the
R_AMP, G_AMP, and B_AMP 8-bit host addressable registers. A synchronization signal can be added to either one, two or all of the RGB signals. The
synchronization signal conforms to NTSC or PAL
specifications.
Some applications (e.g., projection TVs) require
analog component YUV signals. The chip provides
a programmable mode that outputs component
YUV data. Sync can be added to the luminance signal. Independent gain adjustment of the three components is provided as well.
The output of the luma amplifier connects to the
sync insertion block. Sync insertion is accomplished by multiplexing, into the luma data path,
the different sync DC values at the appropriate
times. The digital sync generator takes horizontal
sync and vertical sync timing signals and generates
the appropriate composite sync timing (including
vertical equalization and serration pulses), blanking information, and burst flag. The sync edge rates
conform to RS-170A or ITU R.BT601 and ITU
R.BT470 specifications.
4.7
It is also possible to delay the luminance signal,
with respect to the chrominance signal, by up to
The DACs can be put into tri-state mode via hostaddressable control register bits. Each of the six
DS278F1
Digital to Analog Converters
The CS4954/5 provides six discrete 27 MHz DACs
for analog video. The default configuration is one
10-bit DAC for S-video chrominance, one 10-bit
DAC for S-Video luminance, one 10-bit DAC for
composite output, and three 10-bit DACs for RGB
outputs. All six DACs are designed for driving either low-impedance loads (double terminated
75 Ω) or high-impedance loads (double terminated
300 Ω). There are five different DAC configurations to choose from (see Table 1, below).
13
CS4954 CS4955
DAC
Y
C
Pin #
48
47
Mode 1
Y
C
Mode 2
Y
C
Mode 3
Y
C
Mode 4
CVBS_2
-
Mode 5
CVBS_2
-
CVBS
44
CVBS_1
CVBS_1
CVBS_1
CVBS_1
CVBS_1
R
39
R
Cr (V)
-
R
Cr (V)
G
40
G
Y
CVBS_2
G
Y
B
43
B
Cb (U)
-
B
Cb (U)
Table 1. DAC configuration Modes
DACs has its own associated DAC enable bit. In
the Disable Mode, the 10-bit DACs source (or sink)
zero current.
When running the DACs with a low-impedance
load, a minimum of three DACs must be powered
down. When running the DACs with a high-impedance load, all the DACs can be enabled simultaneously.
For lower power standby scenarios, the CS4954/5
also provides power shut-off control for the DACs.
Each DAC has an associated DAC shut-off bit.
4.8
Voltage Reference
output current modes are software selectable
through a register bit.
4.10 Host Interface
The CS4954/5 provides a parallel 8-bit data interface for overall configuration and control. The host
interface uses active-low read and write strobes,
along with an active-low address enable signal, to
provide microprocessor-compatible read and write
cycles. Indirect host addressing to the CS4954/5 internal registers is accomplished via an internal address register that is uniquely accessible via bus
write cycles in which the host address enable signal
is asserted.
The CS4954/5 is equipped with an on-board voltage reference generator (1.232 V) that is used by
the DACs. The internal reference voltage is accurate enough to guarantee a maximum of 3% overall
gain error on the analog outputs. However, it is
possible to override the internal reference voltage
by applying an external voltage source to the VREF
pin.
The CS4954/5 also provides an I2C-compatible serial interface for device configuration and control.
This port can operate in standard (100Kb/sec) or
fast (400 Kb/sec) modes. When in I2C mode, the
parallel data interface pins, PDAT [7:0], can be
used as a general purpose I/O port controlled by the
I2C interface.
4.9
4.11 Closed Caption Services
Current Reference
The DAC output current-per-bit is derived in the
current reference block. The current step is specified by the size of resistor placed between the ISET
current reference pin and electrical ground.
A 4 kΩ resistor needs to be connected between
ISET pin and GNDA. The DAC output currents are
optimized to either drive a doubly terminated load
of 75 Ω (low impedence mode) or a double terminated load of 300 Ω (high impedence mode). The 2
14
The CS4954/5 supports the generation of NTSC
Closed Caption services. Line 21 and Line 284 captioning can be generated and enabled independently via a set of control registers. When enabled,
clock run-in, start bit, and data bytes are automatically inserted at the appropriate video lines. A convenient interrupt protocol simplifies the software
interface between the host processor and the
CS4954/5.
DS278F1
CS4954 CS4955
4.12 Teletext Services
The CS4954/5 encodes the most common teletext
formats, such as European Teletext, World Standard Teletext (PAL and NTSC), and North American Teletext (NABTS).
Teletext data can be inserted in any of the TV lines
(blanking lines as well as active lines). In addition
the blanking lines can be individually allocated for
Teletext instantiation.
The input timing for teletext data is user programmable. See the section Teletext Services for further
details.
Teletext data can be independently inserted on either one or all of the CVBS_1, CVBS_2, or S-video
signals.
4.13 Wide-Screen Signaling Support and
CGMS
Insertion of wide-screen signal encoding for PAL
and NTSC standards is supported and CGMS
(Copy Generation Management System) for NTSC
in Japan. Wide-screen signals are inserted in lines
23 and 336 for PAL, and lines 20 and 283 for
NTSC.
4.14 VBI Encoding
This chip supports the transmission of control signals in the vertical blanking time interval according
to SMPTE RP 188 recommendations. VBI encoded
data can be independently inserted into either or all
of CVBS_1, CVBS_2 or S-video signals.
4.15 Control Registers
The control and configuration of the CS4954/5 is
accomplished primarily through the control register block. All of the control registers are uniquely
addressable via the internal address register. The
control register bits are initialized during device
RESET.
DS278F1
See the Programming section of this data sheet for
the individual register bit allocations, bit operational descriptions, and initialization states.
4.16 Testability
The digital circuits are completely scanned by an
internal scan chain, thus providing close to 100%
fault coverage.
5.
5.1
OPERATIONAL DESCRIPTION
Reset Hierarchy
The CS4954/5 is equipped with an active low asynchronous reset input pin, RESET. RESET is used to
initialize the internal registers and the internal state
machines for subsequent default operation. See the
electrical and timing specification section of this
data sheet for specific CS4954/5 device RESET
and power-on signal timing requirements and restrictions.
While the RESET pin is held low, the host interface
in the CS4954/5 is disabled and will not respond to
host-initiated bus cycles. All outputs are valid after
a time period following RESET pin low.
A device RESET initializes the CS4954/5 internal
registers to their default values as described by Table 9, Control Registers. In the default state, the
CS4954/5 video DACs are disabled and the device
is internally configured to provide blue field video
data to the DACs (any input data present on the
V [7:0] pins is ignored at this time). Otherwise, the
CS4954/5 registers are configured for NTSC-M
ITU R.BT601 output operation. At a minimum, the
DAC Registers (0x04 and 0x05) must be written (to
enable the DACs) and the IN_MODE bit of the
CONTROL_0 Register (0x01) must be set (to enable ITU R.BT601 data input on V [7:0]) for the
CS4954/5 to become operational after RESET.
15
CS4954 CS4955
N T S C 2 7M H z C loc k C ou nt
P A L 2 7M H z C loc k C ou nt
1682 16 83 1684 1685 1686
1702 17 03 1704 1705 1706
•••
•••
1716
1728
1
1
2
2
3
3
•••
•••
128
128
1 29
•••
1 29
•••
244
264
245
265
246
24 7
266
26 7
248
268
CLK
H S Y N C (in put)
V [7:0]
(S Y N C _D LY =0 )
Y
•••
V [7:0]
(S Y N C _D LY =1 )
Cb
Cr
Y
Cb
a ctiv e pix el
# 720
Y
ac tiv e pixe l
#7 19
Cr
Y
Cr
ac tiv e pixe l
#1
horizo ntal bla nk in g
Cb
Y
ac tiv e pixe l
#72 0
horizo ntal blank ing
Y
ac tiv e p ixel
#2
Cr
Y
ac tiv e pixel
#1
ac tiv e pixel
#2
Figure 4. ITU R.BT601 Input Slave Mode Horizontal Timing
5.2
Video Timing
SYNC_DLY = 0. When SYNC_DLY = 1, it expects
the first active pixel data on clock cycle 246 (NTSC).
5.2.1 Slave Mode Input Interface
In Slave Mode, the CS4954/5 receives signals on
VSYNC and HSYNC as inputs. Slave Mode is the
default following RESET and is changed to Master
Mode via a control register bit (CONTROL_0 [4]).
The CS4954/5 is limited to ITU R.BT601 horizontal and vertical input timing. All clocking in the
CS4954/5 is generated from the CLK pin. In Slave
Mode, the Sync Generator uses externally provided
horizontal and vertical sync signals to synchronize
the internal timing of the CS4954/5. Video data that
is sent to the CS4954/5 must be synchronized to the
horizontal and vertical sync signals. Figure 4 illustrates horizontal timing for ITU R.BT601 input in
Slave Mode. Note that the CS4954/5 expects to receive the first active pixel data on clock cycle 245
(NTSC) when CONTROL_2 Register (0x02) bit
N T S C 27M H z C loc k C o unt
P A L 2 7 M H z C loc k C o unt
1682 1 68 3 1684 1685 1686
1702 1 70 3 1704 1705 1706
•••
•••
1716
1728
1
1
5.2.2 Master Mode Input Interface
The CS4954/5 defaults to Slave Mode following
RESET high but can be switched into Master Mode
via the MSTR bit in the CONTROL_0 Register
(0x00). In Master Mode, the CS4954/5 uses the
VSYNC, HSYNC and FIELD device pins as outputs to schedule the proper external delivery of digital video into the V [7:0] pins. Figure 5 illustrates
horizontal timing for the CCIR601 input in Master
Mode.
The timing of the HSYNC output is selectable in
the PROG_HS Registers (0x0D, 0x0E). HSYNC
can be delayed by one full line cycle. The timing of
the VSYNC output is also selectable in the
2
2
3
3
•••
•••
128
128
1 29
1 29
•••
•••
244
264
245
265
24 6
26 6
2 47
2 67
248
268
CLK
H S Y N C (ou tput)
C B (o utput)
V [7:0]
Y
•••
Cr
Y
activ e pix el
#7 20
Cb
h o rizo n ta l b la n k in g
Y
ac tiv e pix el
#1
Cr
Y
ac tiv e pix el
#2
Figure 5. ITU R.BT601 Input Master Mode Horizontal Timing
16
DS278F1
CS4954 CS4955
PROG_VS Register (0x0D). VSYNC can be delayed by thirteen lines or advanced by eighteen lines.
(falling) edge of HSYNC if the PROG_HS Registers are set to default values.
5.2.3 Vertical Timing
5.2.5 NTSC Interlaced
The CS4954/5 can be configured to operate in any
of four different timing modes: PAL, which is 625
vertical lines, 25 frames per second interlaced;
NTSC, which is 525 vertical lines, 30 frames per
second interlaced; and either PAL or NTSC in Progressive Scan, in which the display is non-interlaced. These modes are selected in the
CONTROL_0 Register (0x00).
The CS4954/5 supports NTSC-M, NTSC-J and
PAL-M modes where there are 525 total lines per
frame and two fixed 262.5-line fields per frame and
30 total frames occurring per second. NTSC interlaced vertical timing is illustrated in Figure 7. Each
field consists of one line for closed caption, 240 active lines of video, plus 21.5 lines of blanking.
The CS4954/5 conforms to standard digital decompression dimensions and does not process digital
input data for the active analog video half lines as
they are typically in the over/underscan region of
televisions. 240 active lines total per field are processed for NTSC, and 288 active lines total per
field are processed for PAL. Frame vertical dimensions are 480 lines for NTSC and 576 lines for
PAL. Table 2 specifies active line numbers for both
NTSC and PAL. Refer to Figure 6 for HSYNC,
VSYNC and FIELD signal timing.
Mode
Field
Active Lines
1, 3;
22-261;
2, 4
285-524
PAL
1, 3, 5, 7;
23-310;
2, 4, 6, 8
336-623
NTSC Progressive-Scan
NA
22-261
PAL Progressive-Scan
NA
23-310
NTSC
Table 2. Vertical Timing
5.2.4 Horizontal Timing
HSYNC is used to synchronize the horizontal-input-to-output timing in order to provide proper horizontal alignment. HSYNC defaults to an input pin
following RESET but switches to an output in Master Mode (CONTROL_0 [4] = 1). Horizontal timing is referenced to HSYNC transitioning low. For
active video lines, digital video input is to be applied to the V [7:0] inputs for 244 (NTSC) or for
264 (PAL) CLK periods following the leading
DS278F1
VSYNC field one transitions low at the beginning
of line four and will remain low for three lines or
2574 pixel cycles (858 × 3). The CS4954/5 exclusively reserves line 21 of field one for closed caption insertion. Digital video input is expected to be
delivered to the CS4954/5 V [7:0] pins for 240
lines beginning on active video lines 22 and continuing through line 261. VSYNC field two transitions low in the middle of line 266 and stays low for
three line-times and transitions high in the middle
of line 269. The CS4954/5 exclusively reserves line
284 of field two for closed caption insertion. Video
input on the V [7:0] pins is expected between lines
285 through line 525.
5.2.6 PAL Interlaced
The CS4954/5 supports PAL modes B, D, G, H, I,
N, and Combination N, in which there are 625 total
lines per frame, two fixed 312.5 line fields per
frame, and 25 total frames per second. Figure 8 illustrates PAL interlaced vertical timing. Each field
consists of 287 active lines of video plus 25.5 lines
of blanking.
VSYNC will transition low to begin field one and
will remain low for 2.5 lines or 2160 pixel cycles
(864 × 2.5). Digital video input is expected to be
delivered to the CS4954/5 V [7:0] pins for 287
lines beginning on active video line 24 and continuing through line 310.
Field two begins with VSYNC transitioning low
after 312.5 lines from the beginning of field one.
17
CS4954 CS4955
N TSC V ertical Tim in g (od d field )
Lin e
3
4
5
6
7
8
9
10
267
26 8
26 9
270
271
3
4
5
6
7
314
31 5
31 6
317
318
HS Y NC
V SY NC
FIE LD
N TSC V ertical Tim in g (even field )
Lin e
2 64
2 65
26 6
HS Y NC
V SY NC
FIE LD
P AL Vertical Tim in g (odd field)
Lin e
2 65
1
2
HS Y NC
V SY NC
FIE LD
P AL V ertical Tim in g (even field )
Lin e
3 11
3 12
31 3
HS Y NC
V SY NC
FIE LD
Figure 6. Vertical Timing
VSYNC stays low for 2.5 line-times and transitions
high with the beginning of line 315. Video input on
the V [7:0] pins is expected between line 336
through line 622.
5.2.7 Progressive Scan
The CS4954/5 supports a progessive scan mode in
which the video output is non-interlaced. This is
accomplished by displaying only the odd video
field for NTSC or PAL. To preserve precise
MPEG-2 frame rates of 30 and 25 per second, the
CS4954/5 displays the same odd field repetitively
but alternately varies the field times. This mode is
in contrast to other digital video encoders, which
18
commonly support progressive scan by repetitively
displaying a 262 line field (524/525 lines for
NTSC). The common method is flawed: over time,
the output display rate will overrun a system-clocklocked MPEG-2 decompressor and display a field
twice every 8.75 seconds.
5.2.8 NTSC Progressive Scan
VSYNC will transition low at line four to begin
field one and will remain low for three lines or
2574 pixel cycles (858 × 3). NTSC interlaced timing is illustrated in Figure 9. In this mode, the
CS4954/5 expects digital video input at the V [7:0]
DS278F1
CS4954 CS4955
Analog
Field 1
523
524
525
1
VS YN C D ro p s
2
3
4
5
6
7
8
9
10
22
Analog
Fie ld 2
2 61
262
2 63
26 4
2 65
2 66
Analog
Fie ld 3
523
5 24
525
1
26 7
268
269
270
2 71
27 2
2 84
2 85
VS YN C D ro p s
2
3
4
5
6
7
8
9
10
22
Analog
Fie ld 4
2 61
262
2 63
26 4
2 65
2 66
26 7
268
B u rs t be g in s w ith p o sitiv e h alf-c y c le
269
270
2 71
27 2
2 84
2 85
Bu r st b e gin s w ith n e g a tiv e h a lf-c y cle
Figure 7. NTSC Video Interlaced Timing
pins for 240 lines beginning on active video line 22
and continuing through line 261.
Field two begins with VSYNC transitioning low at
line 266. VSYNC stays low for 3 line cycles and
transitions high during the end of line 268. Video
input on the V [7:0] pins is expected between line
284 and line 522. Field two is 263 lines; field one
is 262 lines.
5.2.9 PAL Progressive Scan
VSYNC will transition low at the beginning of the
odd field and will remain low for 2.5 lines or 2160
pixel cycles (864 × 2.5). PAL non-interlaced timing is illustrated in Figure 10. In this mode, the
CS4954/5 expects digital video input on the V [7:0]
pins for 288 lines, beginning on active video line 23
and continuing through line 309.
The second begins with VSYNC transitioning low
after 312 lines from the beginning of the first field.
VSYNC stays low for 2.5 line-times and transitions
DS278F1
high during the middle of line 315. Video input on
the V [7:0] pins is expected between line 335
through line 622. Field two is 313 lines; field one is
312 lines.
5.3
ITU-R.BT656
The CS4954/5 supports an additional ITUR.BT656 slave mode feature that is selectable
through the ITU-R.BT656 bit of the CONTROL_0
Register. The ITU-R.BT656 slave feature is unique
because the horizontal and vertical timing and digital video are combined into a single 8-bit 2 7MHz
input. With ITU-R.BT656 there are no horizontal
and vertical input or output strobes, only 8-bit
27 MHz active CbYCrY data, with start- and endof-video codes implemented using reserved 00 and
FF code sequences within the video feed. As with
all modes, V [7:0] are sampled with the rising edge
of CLK. The CS4954/5 expects the digital ITUR.BT656 stream to be error-free. The FIELD out-
19
CS4954 CS4955
VS Y N C D ro p s
Analog
Field 1
62 0
62 1
62 2
623
6 24
625
1
2
3
4
5
6
7
23
24
Analog
F ie ld 2
30 8
30 9
310
311
312
313
3 14
31 5
3 16
317
318
31 9
3 20
3 36
337
Analog
F ie ld 3
62 0
62 1
62 2
6 24
623
625
1
2
3
4
5
6
7
23
24
Analog
F ie ld 4
30 8
30 9
310
311
312
313
3 14
31 5
3 16
317
318
31 9
3 20
3 36
337
Analog
F ie ld 5
62 1
62 0
62 2
623
6 24
625
1
2
3
4
5
6
7
23
24
Analog
F ie ld 6
30 8
30 9
310
311
312
313
3 14
31 5
3 16
317
318
31 9
3 20
3 36
337
Analog
F ie ld 7
62 0
62 1
62 2
6 24
623
625
1
2
3
4
5
6
7
23
24
Analog
F ie ld 8
30 8
30 9
310
311
312
313
3 14
31 5
B u rs t P h a se = 1 3 5 d e g re e s re lativ e to U
3 16
317
318
31 9
3 20
3 36
337
B ur s t Ph as e = 22 5 d e g re e s re la tiv e t o U
Figure 8. PAL Video Interlaced Timing
put toggles as with non ITU-R.BT656 input. ITUR.BT656 input timing is illustrated in Figur e11.
As mentioned above, there are no horizontal and
vertical timing signals necessary in ITU-R.BT656
mode. However in some cases it is advantageous to
20
output these timing signals for other purposes. By
setting the 656_SYNC_OUT register bit in
CONTROL_6 register, HSYNC and VSYNC are
output,so that other devices in the system can synchronize to these timing signals.
DS278F1
CS4954 CS4955
S tart of
V SYN C
262
2 63
1
2
3
F ie ld 1
4
5
6
7
8
9
10
22
6
7
8
9
10
22
6
7
8
9
10
22
6
7
8
9
10
22
F ie ld 2
261
2 62
1
2
3
4
5
S ta rt o f
V SY N C
262
2 63
1
2
3
F ie ld 3
4
5
F ie ld 4
261
2 62
1
2
3
4
5
B urst begins with po sitiv e half-c ycle
Bur s t be gin s with n ega tiv e h alf- c y c le
B u rst pha se = refere n ce ph as e = 1 8 0 0 r ela tiv e to B -Y
Bur s t ph as e = re fere nc e p has e = 1 8 0 0 re lativ e to B -Y
Figure 9. NTSC Video Non-Interlaced Progressive Scan Timing
VS Y N C D ro ps
Analog
Field 1
30 9
31 0
311
3 12
313
1
2
3
4
5
6
7
23
24
2
3
4
5
6
7
23
24
2
3
4
5
6
7
23
24
2
3
4
5
6
7
23
24
Analog
F ield 2
3 08
30 9
31 0
311
312
1
Analog
F ield 3
30 9
31 0
311
3 12
313
1
Analog
F ield 4
3 08
30 9
31 0
311
312
1
Bu rst P ha se = 135 d egree s re lative to U
B urst P hase = 225 de gre es re lativ e to U
Figure 10. PAL Video Non-Interlaced Progressive Scan Timing
DS278F1
21
CS4954 CS4955
Composite
Video
ITU R.BT656
V[7:0]
DATA
Y
Cr
Y FF 00 00 XY 80 10 80 10
EAV Code
80 10 80 10 80 10
Ancilliary Data
80 10 80 10 FF 00 00 XY Cb Y Cr Cb Y Cr
268 Clocks (NTSC)
280 Clocks (PAL)
4 Clocks
Active Video
SAV Code
4 Clocks
1440 Clocks
Active Video
Horizontal Blanking
Figure 11. CCIR656 Input Mode Timing
5.4
Digital Video Input Modes
The CS4954/5 provides two different digital video
input modes that are selectable through the
IN_MODE bit in the CONTROL_0 Register.
In Mode 0 and upon RESET, the CS4954/5 defaults to output a solid color (one of a possible of
256 colors). The background color is selected by
writing the BKG_COLOR Register (0x08). The
colorspace of the register is RGB 3:3:2 and is unaffected by gamma correction. The default color following RESET is blue.
In Mode 1 the CS4954/5 supports a single 8-bit
27 MHz CbYCrY source as input on the V [7:0]
pins. Input video timing can be ITU-R.BT601 master or slave and ITU-R.BT656.
5.6
Subcarrier Generation
The CS4954/5 automatically synthesizes NTSC
and PAL color subcarrier clocks using the CLK frequency
and
four
control
registers
(SC_SYNTH0/1/2/3). The NTSC subcarrier synthesizer is reset every four fields (every eight fields
for PAL).
The SC_SYNTH0/1/2/3 registers used together
provide a 32-bit value that defaults to NTSC
(43E0F83Eh) following RESET. Table 4 shows the
32-bit value required for each of the different
broadcast formats.
System
NTSC-M, NTSC-J
Fsubcarrier
Value (hex)
3.5795455 MHz
43E0F83E
PAL-B, D, G, H, I, N 4.43361875 MHz 54131596
5.5
Multi-standard Output Format Modes
The CS4954/5 supports a wide range of output formats compatible with worldwide broadcast standards. These formats include NTSC-M, NTSC-J,
PAL-B/D/G/H/I, PAL-M, PAL-N, and PAL Combination N (PAL-Nc) which is the broadcast standard used in Argentina. After RESET, the CS4954/5
defaults to NTSC-M operation with ITU R.BT 601
analog timing. NTSC-J can also be supported in the
Japanese format by turning off the 7.5 IRE pedestal
through the PED bit in the CONTROL_1 Register
(0x01).
Output formats are configured by writing control
registers with the values shown in Table 3.
22
PAL-N (Argentina)
3.582056 MHz
43ED288D
PAL-M
3.579611 MHz
43CDDFC7
Table 3.
5.7
Subcarrier Compensation
Since the subcarrier is synthesized from CLK the
subcarrier frequency error will track the clock frequency error. If the input clock has a tolerance of
200 ppm then the resulting subcarrier will also
have a tolerance of 200 ppm. Per the NTSC specification, the final subcarrier tolerance is ±10 Hz
which is approximately 3 ppm. Care must be taken
in selecting a suitable clock source.
DS278F1
CS4954 CS4955
In MPEG-2 system environments the clock is actually recovered from the data stream. In these cases
the recovered clock can be 27 MHz ±50 ppm or
±1350 Hz. It varies per television, but in many cases given an MPEG-2 system clock of 27 MHz,
±1350 Hz, the resultant color subcarrier produced
will be outside of the television’s ability to compensate and the chrominance information will not
be displayed (resulting in a black-and-white picture
only).
The CS4954/5 is designed to provide automatic
compensation for an excessively inaccurate
MPEG-2 system clock. Sub-carrier compensation
is enabled through the XTAL bit of the
CONTROL_2 Register. When enabled the
CS4954/5 will utilize a common quartz color burst
crystal (3.579545 MHz ± 50 ppm for NTSC) attached to the XTAL_IN and XTAL_OUT pins to
automatically compare and compensate the color
subcarrier synthesis process.
5.8
Closed Caption Insertion
The CS4954/5 is capable of NTSC Closed Caption
insertion on lines 21 and 284 independently.
Closed captioning is enabled for either one or both
lines via the CC_EN [1:0] Register bits and the
data to be inserted is also written into the four
Closed Caption Data registers. The CS4954/5,
when enabled, automatically generates the seven
cycles of clock run-in (32 times the line rate), start
bit insertion (001), and finally insertion of the two
data bytes per line. Data low at the video outputs
corresponds to 0 IRE and data high corresponds to
50 IRE.
There are two independent 8-bit registers per line
(CC_21_1 & CC_21_2 for line 21 and CC_284_1
& CC_284_2 for line 284). Interrupts are also provided to simplify the handshake between the driver
software and the device. Typically the host would
write all 4 bytes to be inserted into the registers and
then enable closed caption insertion and interrupts.
As the closed caption interrupts occur the host software would respond by writing the next two bytes
to be inserted to the correct control registers and
then clear the interrupt and wait for the next field.
5.9
Programmable H-sync and V-sync
It is possible in master mode to change the H-sync
and V-sync times based on register settings. Programmable H-sync and V-sync timings are helpful
in several digital video systems, where latencies of
the control signals are present. The user can then
program H-sync and V-sync timing according to
their system requirements. The default values are
244, and 264 for NTSC and PAL respectively.
H-sync can be delayed by a full line, in 74 nsec intervals.
NTSC-M NTSC-J
ITU
ITU
NTSC-M
PALR.BT601 R.BT601 RS170A B,D,G,H,I
PAL-M
PAL-N
PAL-N
Comb.
(Argent)
41h
61h
A1h
81h
30h
12h
30h
30h
07h
07h
07h
07h
07h
78h
78h
78h
78h
78h
78h
1Ch
1Ch
1Ch
15h
15h
15h
15h
3Eh
3Eh
3Eh
96h
C7h
96h
8Ch
SC_SYNTH1
F8h
F8h
F8h
15h
DFh
15h
28h
0×13
SC_SYNTH2
E0h
E0h
E0h
13h
CDh
13h
EDh
0×14
SC_SYNTH3
43h
43h
43h
54h
43h
54h
43h
Address
Register
0×00
CONTROL_0
01h
01h
21h
0×01
CONTROL_1
12h
10h
16h
0×04
CONTROL_4
07h
07h
0×05
CONTROL_5
78h
0×10
SC_AMP
0×11
SC_SYNTH0
0×12
Table 4. Multi-standard Format Register Configurations
DS278F1
23
CS4954 CS4955
V-sync can be shifted in both directions in time.
The default values are 18 and 23 for NTSC and
PAL respectively. Since the V-sync register is 5
bits wide (Sync Register 0), the V-sync pulse can
be shifted by 31 lines in total.
V-sync can preceed by a maximum of 18 lines
(NTSC) or 23 lines (PAL) respectively from its default location, and V-sync can follow by a maximum of 13 lines (NTSC) or 8 lines (PAL) from its
default location.
5.10 Wide Screen Signaling (WSS) and
CGMS
Wide screen signaling support is provided for
NTSC and for PAL standards. Wide screen signaling is currently used in most countries with 625 line
systems as well as in Japan for EDTV-II applications. For complete description of WSS standard,
please refer to ITU-R BT.1119 (625 line system)
and to EIAJ CPX1204 for the Japanese 525 line
system.
The wide screen signal is transferred in a blanking
line of each video field (NTSC: lines 20 and 283,
PAL: lines 23 and 336). Wide screen signaling is
enabled by setting WW_23 to “1”. Some countries
with PAL standard don’t use line 336 for wide
screen signaling (they use only line 23), therefore
we provide another enable bit (WSS_22) for that
particular line.
There are 3 registers dedicated to contain the transmitted WSS bits (WSS_REG_0, WSS_REG_1,
WSS_REG_2). The data insertion into the appropriate lines are performed automatically by this device. The run-in and start code bits do not have to
be loaded into this device, it automatically inserts
the correct code at the beginning of transfer.
All these teletext standards are defined in the ITUR BT.653-2 document. The European teletext is
defined as “teletext system B” for 625/50 Hz TV
systems. NABTS teletext is defined as “teletext
system C” for 525/60 Hz TV systems. WST for
PAL is defined as “teletext system D” for
624/50 Hz TV systems and WST for NTSC is defined as “teletext system D” for 525/60 Hz TV
systems.
This chip provides independant teletext encoding
into composite 1, composite 2 and s-video signals.
The teletext encoding into these various signals is
software programmable.
In teletext pulsation mode, (TTX_WINDOW=0),
register 0×31 bit 3, the pin TTXDAT receives a
teletext bitstream sampled at the 2 7Mhz clock. At
each rising edge of the TTXRQ output signal a single teletext bit has to be provided after a programmable input delay at the TTXDAT input pin.
Phase variant interpolation is achieved on this bitstream in the internal teletext encoder, providing
sufficient small phase jitter on the ouput text lines.
TTXRQ provides a fully programmable request
signal to the teletext source, indicating the insertion
period of the bitstream at indepenantly selectable
lines for both TV fields. The internal insertion window for text is set to either 360, 296 or 288 teletext
bits, depending on the selected teletext standard.
The clock run-in is included in this window.
Teletext in enabled by setting the TTX_EN bit to
“1”. The TTX_WST bit in conjunction with the
TV_FORMAT register select one of the 4 possible
teletext encoding possibilities.
5.11 Teletext Support
The teletext timing is shown in the Figure 12.
TTXHS and TTXHD are user programmable and
therefore allow the user to have full control over to
when sending teletext data to this device.
This chip supports several teletext standards, like
European teletext, NABTS (North American teletext), and WST (World Standard Teletext) for
NTSC and PAL.
The time tFD is the time needed to interpolate teletext input data and inserting it into the CVBS and
Y output signals, such that it appears between
tTTX = 9.8 µs and tTTX = 12 µs after the leading
24
DS278F1
CS4954 CS4955
edge of the horizontal synchronization pulse. tFD
changes with the TV standard and the selected
teletext standard. Please refer to ITU-R BT.653-2
for more detailed information.
The time tPD is the pipeline delay time introduced
by the source that is gated by TTXRQ in order to
deliver teletext data. This delay is programmable
through the register TTXHD. For every active
HIGH transition at output pin TTXRQ, a new teletext bit must be provided by the source. The time
between the beginning of the first TTXRQ pulse
and the leading edge of H-sync is programmable
through the TTXHS register.
Since the beginning of the pulses representing the
TTXRQ signal and the delay between the rising
edge of TTXRQ and valid teletext input data are
fully programmable, the TTXDAT data is always
inserted at the correct position after the leading
edge of the outgoing horizontal synchronization
pulse.
The time tTTXWin is the internally used insertion
window for TTX data; it has a constant length
depending on the selected teletext standard which
allows insertion of 360 TTX bits (6.9375
Mbit/sec) (European teletext) or 296 TTX bits
(5.6427875 Mbit/sec) (WST PAL) or 288 TTX bits
(5.727272 Mbit/sec) (NABTS) or 296 TTX bits
(5.727272 Mbit/sec) (WST NTSC) respectively.
Using the appropriate programming, all suitable
lines of the odd field (TTXOVS through TTXOVE) plus all suitable lines of the even field
CVBS/Y
(TTXEVS through TTXEVE) can be used for teletext insertion. In addition it is possible to selectively disable the teletext insertion on single lines.
This can be programmed by setting the
TTX_LINE_DIS1,
TTX_LINE_DIS2
and
TTX_LINE_DIS3 registers appropriately.
Note that the TTXDAT signal must be synchronized with the 27 Mhz clock. The pulse width of
the TTXRQ signal varies between three and four
27 Mhz clock cycles. The variation is necessary in
order to maintain the strict timing requirements of
the teletext standard.
Table 5 shows how to program the TTXHS register
for teletext instantiation into the analog signals for
the various supported TV formats. TTXHS is the
time between the leading edge of the HSYNC signal and the rising edge of the first TTXRQ signal
and consists of multiples of 27 Mhz clock cycles
Note that with increasing values of TTXHS the
time tTTX increases as well. The time t FD accounts
for the internal pipeline delay due to processing,
synchronization and instantiation of the teletext
data. The time tPD is dependant on the TTXHD
register.
Note that the teletext databits are shaped according
to the ITU R.BT653-2 specifications.
If register 0×31 bit 3 is set, (TTX_WINDOW=1)
the teletext is in windows mode, the request pulses
CVBS/Y
tTTXWin
tTTX
TTXRQ
tTTXWin
tTTX
TTXRQ
textbit #: 1
2
3
4
TTXDAT
5
textbit #: 1
2
3
4
5
TTXDAT
tPD
tFD
Figure 12. Teletext Timing (Pulsation Mode)
DS278F1
tPD
tFD
Figure 13. Teletext Timing (Window Mode)
25
CS4954 CS4955
become a window where the bit provided on the
TTXDAT pin are valid (see Figure 13).
Alternately to the pulsation mode (where the number of request pulses are determined by the teletext
standard chosen), the length of the window must be
programmed by the user independently of the teletext standard used. The length of the window is
programmed through register 0×29 TTXHS (start
of window) and register 0×2A (TTXHD) and 0×31
(end of window). The end-of-window register is a
11 bit value.
In teletext window mode, the TTXHS value can be
selected using the values in Table 5. Although
these values may need to be adjusted to match your
system delay, use the following equation to compute the TTXHD value:
TTXHS + 1402 = TTXHD (for Europe)
TTXHS + 1151 = TTXHD (for WST)
TTXHS + 1122 = TTXHD (for NABTS)
TV standard
NTSC-M
NTSC-M
PAL-B
PAL-B
PAL-M
PAL-M
PAL-N (non Arg.)
PAL-N (non Arg.)
PAL-N (Arg.)
PAL-N (Arg.)
Teletext
standard
NABTS
WST-NTSC
Europe TTX
WST-PAL
NABTS
WST-NTSC
Europe TTX
WST-PAL
Europe TTX
WST-PAL
TTXHS
(register
value)
161
142
204
163
161
142
204
163
204
163
tTTX
10.5 µs
9.8 µs
12.0 µs
10.5 µs
10.5 µs
9.8 µs
12.0 µs
10.5 µs
12.0 µs
10.5 µs
Table 5. Teletext timing parameters
5.12 Color Bar Generator
The CS4954/5 is equipped with a color bar generator that is enabled through the CBAR bit of the
CONTROL_1 Register. The color bar generator
works in master or Slave Mode and has no effect on
the video input/output timing. If the CS4954/5 is
26
configured for Slave Mode color bars, proper video
timing must be present on the HSYNC and
VSYNC pins for the color bars to be displayed.
Given proper Slave Mode input timing or Master
Mode, the color bar generator will override the video input pixel data.
The output of the color bar generator is instantiated
after the chroma interpolation filter and before the
luma delay line. The generated color bar numbers
are for 100% amplitude, 100% saturation NTSC
EIA color bars or 100% amplitude, 100% saturation PAL EBU color bars. For PAL color bars, the
CS4954/5 generates NTSC color bar values, which
are very close to standard PAL values. The exact
luma and chroma values are listed in Table 6. .
Color
White
Yellow
Cyan
Green
Magenta
Red
Blue
Black
Cb
0
- 84
+ 28
- 56
+ 56
- 28
+ 84
0
Cr
0
+ 14
- 84
- 70
+ 70
+ 84
- 14
0
Y
+ 167
+ 156
+ 138
+ 127
+ 110
+ 99
+ 81
+ 70
Table 6. Internal Color Bar Values (8-bit values, Cb/Cr are in twos
complement format)
5.13 VBI encoding
VBI (Vertical Blanking Interval) encoding is performed according to SMPTE RP 188 recommendations. In NTSC mode lines 10 - 20 and lines 272 283 are used for the transmission of ancillary data.
In PAL mode lines 6 - 22 and lines 318 -335 are
used. The VBI encoding mode can be set through
the CONTROL_3 register.
All digital input data is passed through the chip
when this mode is enabled. It is therefore the responsibility of the user to ensure appropriate amplitude levels. Table 7 shows the relationship of the
digital input signal and the analog output voltage.
DS278F1
CS4954 CS4955
Digital Input
Analog Output Voltage
0×38
286 mV
0×3B
300 mV
0×C4
1000 mV
Table 7. VBI Encoding Signal Amplitudes
Each LSB corresponds to a step of 5 mV in the output voltage.
5.14 Super White/Super Black support
The ITU-R BT.601 recommendation limits the allowed range for the digital video data between
0×10 - 0×EB for luma and between 0×10 - 0×F0 for
the chrominance values. This chip will clip any
digital input value which is out of this range to conform to the ITU-R BT.601 specifications.
However for some applications it is useful to allow
a wider input range. By setting the CLIP_OFF bit
(CONTROL_6 register) the allowed input range is
extended between 0×01 - 0×FE for both luma and
chrominance values.
Note that 0×00 and 0×FF values are never allowed,
since they are reserved for synchronization information.
5.15 Interrupts
In order to better support precise video mode
switches and to establish a software/hardware
handshake with the closed caption insertion block
the CS4954/5 is equipped with an interrupt pin
named INT. The INT pin is active high. There are
three interrupt sources: VSYNC, Line 21, and Line
284. Each interrupt can be individually disabled
with the INT_EN Register. Each interrupt is also
cleared via writing a one to the corresponding
INT_CLR Register bits. The three individual inter-
DS278F1
rupts are OR-ed together to generate an interrupt
signal which is presented on the INT output pin. If
an interrupt has occurred, it cannot be eliminated
with a disable, it must be cleared.
5.16 General Purpose I/O Port
The CS4954/5 has a GPIO port and register that is
available when the device is configured for I2C
host interface operation. In I2C host interface
mode, the PDAT [7:0] pins are unused by the host
interface and they can operate as input or output
pins for the GPIO_DATA_REG Register (0×0A).
The
CS4954/5
also
contains
the
GPIO_CTRL_REG Register (0×09) which is used
to configure the GPIO pins for input or output operation.
The GPIO port PDAT [7:0] pins are configured for
input operation when the corresponding
GPIO_CTRL_REG [7:0] bits are set to 0. In GPIO
input mode, the CS4954/5 will latch the data on the
PDAT [7:0] pins into the corresponding bit locations of GPIO_DATA_REG when it detects register address 0×0A through the I2C interface. A
detection of address 0×0A can happen in two ways.
The first and most common way this will happen is
when address 0×0A is written to the CS4954/5 via
its I2C interface. The second method for detecting
address 0×0A is implemented by accessing register
address 0×09 through I2C. In I2C host interface operation, the CS4954/5 register address pointer will
auto-increment to address 0×0A after an address
0×09 access.
The GPIO port PDAT [7:0] pins are configured for
output operation when the corresponding
GPIO_CTRL_REG [7:0] bits are set. In GPIO output mode, the CS4954/5 will output the data in
GPIO_DATA_REG [7:0] bit locations onto the
corresponding PDAT [7:0] pins when it detects a
register address 0×0A through the I2C interface.
27
CS4954 CS4955
6. FILTER RESPONSES
1.3 Mhz. filter passband response
1.3 Mhz. filter frequency response
0
-10
0
magnitude - dB
magnitude - dB
-20
-30
-40
-0.1
-0.2
-0.3
-50
-0.4
-60
-70
0
1
2
3
4
frequency (Hz)
5
6
-0.5
6
x 10
Figure 14. 1.3 Mhz Chrominance low-pass filter transfer characteristic
0
2
4
6
frequency (Hz)
10
12
x 10 5
Figure 15. 1.3 Mhz Chrominance low-pass filter transfer characterstic (passband)
650 Khz. filter passband response
650 Khz. filter frequency response
0
0
-0.5
magnitude - dB
-5
magnitude - dB
8
-10
-15
-1
-1.5
-2
-20
-2.5
-25
-3
-30
0
1
2
3
4
5
0
6
x 10
6
Figure 16. 650 kHz Chrominance low-pass filter transfer characteristic
28
2
4
6
8
10
12
x 10
5
Figure 17. 650 kHz Chrominance low-pass filter transfer characteristic (passband)
DS278F1
CS4954 CS4955
Luma Output Interpolation Filter Response at 27MHz full scale
Chroma Output Interpolator Pass band
1
0
0.8
-5
Magnitude Response (dB)
Magnitude Response (dB)
0.6
0.4
0.2
0
-0.2
-0.4
-10
-15
-20
-25
-30
-0.6
-35
-0.8
-1
-40
0
0.5
1
1.5
2
2.5
3
Frequency (MHz)
3.5
4
4.5
0
5
Figure 18. Chrominance output interpolation filter transfer characteristic (passband)
2
0
-5
Magnitude Response (dB)
Magnitude Response (dB)
0
-0.5
-1
-1.5
-2
-20
-25
-3
-35
3
4
5
Frequency (MHz)
6
7
8
Figure 20. Luminance interpolation filter transfer characterstic
(passband)
DS278F1
14
-15
-30
2
12
-10
-2.5
1
10
RGB datapath filter for rgb_bw = 0 full scale
Luma Output Interpolation Filter Response at 27 MHz (-3 dB)
0
6
8
Frequency (MHz)
Figure 19. Luminance interpolation filter transfer characteristic
0.5
-3.5
4
-40
0
2
4
6
8
Frequency (MHz)
10
12
Figure 21. Chrominance interpolation filter transfer characteristic
for RGB datapath
29
CS4954 CS4955
RGB datapath filter when rgb_bw = 1 (Reduced Bandwidth)
0
0.5
-5
0
-10
Magnitude Response (dB)
Magnitude Response (dB)
RGB datapath filter when rgb_bw = 1 (Reduced Bandwidth) (-3 dB)
1
-0.5
-1
-1.5
-2
-20
-25
-30
-35
-2.5
-3
-15
-40
0
2
4
6
8
Frequency (MHz)
10
12
Figure 22. Chroma Interpolator for RGB Datapath when
rgb_bw=1 (Reduced Bandwidth)
-45
0
2
4
6
8
Frequency (MHz)
10
12
Figure 23. Chroma Interpolator for RGB Datapath when
rgb_bw=1 (Reduced Bandwidth)
RGB datapath filter for rgb_bw = 0 (-3 dB)
Chroma Output Interpolator Full Scale
1
0
0.5
Magnitude Response (dB)
Magnitude Response (dB)
-5
0
-0.5
-1
-1.5
-15
-20
-25
-2
-30
-2.5
-35
-3
0
2
4
6
8
Frequency (MHz)
10
12
Figure 24. Chroma Interpolator for RGB Datapath when
rgb_bw=0 -3 dB
30
-10
-40
0
5
10
15
Frequency (MHz)
20
25
Figure 25. Chroma Interpolator for RGB Datapath when
rgb_bw=0 (Full Scale)
DS278F1
CS4954 CS4955
7.
7.1
ANALOG
Analog Timing
All CS4954/5 analog timing and sequencing is derived from 27 MHz clock input. The analog outputs
are controlled internally by the video timing generator in conjunction with master and slave timing. The
video output signals perform accordingly for NTSC
and PAL specifications.
Being that the CS4954/5 is almost entirely a digital
circuit, great care has been taken to guarantee analog timing and slew rate performance as specified
in the NTSC and PAL analog specifications. Reference the Analog Parameters section of this data
sheet for exact performance parameters.
7.2
VREF
The CS4954/5 can operate with or without the aid
of an external voltage reference. The CS4954/5 is
designed with an internal voltage reference generator that provides a VREFOUT signal at the VREF
pin. The internal voltage reference is utilized by not
making a connection to the VREF pin. The VREF
pin can also be connected to an external precision
1.232 volt reference, which then overrides the internal reference.
7.3
ISET
All six of the CS4954/5 digital to analog converter
DACs are output current normalized with a common ISET device pin. The DAC output current per
bit is determined by the size of the resistor connected between ISET and electrical ground. Typically a
4 KΩ, 1% metal film resistor should be used. The
ISET resistance can be changed by the user to accommodate varying video output attenuation via
post filters and also to suit individual preferred performance.
In conjunction with the ISET value, the user can
also independently vary the chroma, luma and colorburst amplitude levels via host addressable control register bits that are used to control internal
DS278F1
digital amplifiers. The DAC output levels are defined by the following operations:
VREF/RISET = IREF
(e.g., 1.232 V/4K Ω = 308 µA)
CVBS/Y/C/R/G/B outputs in low impedance mode:
VOUT (max) = IREF*(16/145)*1023*37.5 Ω = 1.304V
CVBS/Y/C/R/G/B outputs in high impedance mode:
VOUT (max) = IREF*(4/145)*1023*150Ω = 1.304 V
7.4
DACs
The CS4954/5 is equipped with six independent,
video-grade, current-output, digital-to-analog converters (DACs). They are 10-bit DACs operating at
a 27 MHz two-times-oversampling rate. All six
DACs are disabled and default to a low power
mode upon RESET. Each DAC can be individually
powered down and disabled. The output-currentper-bit of all six DACs is determined by the size of
the resistor connected between the ISET pin and
electrical ground.
7.4.1 Luminance DAC
The Y pin is driven from a 10-bit 27 MHz current
output DAC that internally receives the Y, or luminance portion, of the video signal (black and white
only). Y is designed to drive proper video levels
into a 37.5 Ω load. Reference the detailed electrical
section of this data sheet for the exact Y digital to
analog AC and DC performance data. A EN_L enable control bit in the Control Register 5 (0×05) is
provided to enable or disable the luminance DAC.
For a complete disable and lower power operation
the luminance DAC can be totally shut down via
the SVIDLUM_PD control bit in the Control Register 4 (0×04). In this mode, turn-on through the control register will not be instantaneous.
7.4.2 Chrominance DAC
The C pin is driven from a 10-bit 27 MHz current
output DAC that internally receives the C or
31
CS4954 CS4955
chrominance portion of the video signal (color
only). C is designed to drive proper video levels
into a 37.5 Ω load. Reference the detailed electrical
section of this data sheet for the exact C digital to
analog AC and DC performance data. A EN_C enable control register bit in the Control Register 1
(0×05) is provided to enable or disable the chrominance DAC. For a complete disable and lower
power operation the chrominance DAC can be totally shut down via the SVIDCHR_PD register bit
in the Control Register 4 (0×04). In this mode turnon through the control register will not be instantaneous.
7.4.3 CVBS DAC
The CVBS pin is driven from a 10-bit 27 MHz current output DAC that internally receives a combined luma and chroma signal to provide
composite video output. CVBS is designed to drive
proper composite video levels into a 37.5 Ω load.
Reference the detailed electrical section of this data
sheet for the exact CVBS digital to analog AC and
DC performance data. The EN_COM enable control register bit, in Control Register 1 (0×05), is
provided to enable or disable the output pin. When
disabled, there is no current flow from the output.
For a complete disable and lower power operation,
the CVBS37 DAC can be totally shut down via the
COMDAC_PD control register bit in Control
Register 4 (0×04). In this mode turn-on through the
control register will not be instantaneous.
7.4.4 Red DAC
The Red pin is driven from a 10-bit 27 MHz current
output DAC that internally receives a combined
luma and chroma signal to provide composite video output. Red is designed to drive proper composite video levels into a 37.5 Ω load. Reference the
detailed electrical section of this data sheet for the
exact red digital to analog AC and DC performance
data. The EN_R enable control register bit, in Control Register 1 (0×05), is provided to enable or disable the output pin. When disabled, there is no
32
current flow from the output. For a complete disable and lower power operation, the red DAC can
be totally shut down via the R_PD control register
bit in Control Register 4 (0×04). In this mode turnon through the control register will not be instantaneous.
7.4.5 Green DAC
The green pin is driven from a 10-bit 2 7MHz current output DAC that internally receives a combined luma and chroma signal to provide
composite video output. Green is designed to drive
proper composite video levels into a 37.5 Ω load.
Reference the detailed electrical section of this data
sheet for the exact green digital to analog AC and
DC performance data. The EN_G enable control
register bit, in Control Register 1 (0×05), is provided to enable or disable the output pin. When disabled, there is no current flow from the output. For
a complete disable and lower power operation, the
green DAC can be totally shut down via the G_PD
control register bit in Control Register 4 (0×04). In
this mode turn-on through the control register will
not be instantaneous.
7.4.6 Blue DAC
The blue pin is driven from a 10-bit 27 MHz current output DAC that internally receives a combined luma and chroma signal to provide
composite video output. Blue is designed to drive
proper composite video levels into a 37.5 Ω load.
Reference the detailed electrical section of this data
sheet for the exact blue digital to analog AC and
DC performance data. The EN_B enable control
register bit, in Control Register 5 (0×05), is provided to enable or disable the output pin. When disabled, there is no current flow from the output. For
a complete disable and lower power operation, the
blue DAC can be totally shut down via the B_PD
control register bit in Control Register 4 (0×04). In
this mode turn-on through the control register will
not be instantaneous.
DS278F1
CS4954 CS4955
If some of the 6 DACs are not used, it is strongly
recommended to power them down (see
CONTROL_4 register) in order to reduce the power dissipation.
Low/High
Impedance
mode
maximum # of
active DACs
3.3V
Low Impedance
3
3.3V
High Impedance
6
5.0V
Low Impedance
3
5.0V
High Impedance
6
Nominal Power
supply
Depending on the external resistor connected to the
ISET pin the output drive of the DACs can be
changed. There are two modes in which the DACs
should either be operated in. An external resistor of
4 kΩ must be connected to the ISET pin.
Table 8. Maximum DAC Numbers
8.
The first mode is the high impedance mode
(LOW_IMP bit set to 0). The DAC outputs will
then drive a double terminated load of 300 Ω and
will output a video signal which conforms to the
analog video specifications for NTSC and PAL.
External buffers will be needed if the DAC output
load differs from 3 0 0Ω.
PROGRAMMING
8.1
Host Control Interface
The CS4954/5 host control interface can be configured for I2C or 8-bit parallel operation. The
CS4954/5 will default to I2C operation when the
RD and WR pins are both tied low at power up. The
RD and WR pins are active for 8-bit parallel operation only.
The second mode is the low impedence mode
(LOW_IMP but set to 1). The DAC output will
then drive a double terminated load of 75 Ω and
will output a video signal which conforms to the
analog video specifications for NTSC and PAL. No
external buffers are necessary, the ouputs can directly drive a television input.
8.1.1 I2C Interface
The CS4954/5 provides an I2C interface for accessing the internal control and status registers. External pins are a bidirectional data pin (SDA) and a
serial input clock (SCL). The protocol follows the
I2C specifications. A complete data transfer is
shown in Figure 26. Note that this I2C interface will
work in Slave Mode only - it is not a bus master.
Note that for power dissipation purposes it is not
always possible to have all the 6 DACs active at the
same time. Table 8 shows the maximum allowed
active DACs depending on the power supply and
low/high impedance modes. If less than 6 DACs
are allowed to be active the other ones must be
power down (see CONTROL_4 register).
SDA and SCL are connected via an external pullup resistor to a positive supply voltage. When the
bus is free, both lines are high. The output stages of
devices connected to the bus must have an opendrain or open-collector in order to perform the
wired-AND function. Data on the I2C bus can be
SDA
SCL
A
Start
1-7
8
Address R/W
9
ACK
1-7
8
Data
9
ACK
1-7
8
9
P
Data ACK
Stop
Note: I 2C transfers data always with MSB first, LSB last
Figure 26. I2C Protocol
DS278F1
33
CS4954 CS4955
transferred at a rate of up to 400 Kbits/sec in fast
mode. The number of interfaces to the bus is solely
dependent on the limiting bus capacitance of 400
pF. When 8-bit parallel interface operation is being
used, SDA and SCL can be tied directly to ground.
The I2C bus address for the CS4954/5 is programmable via the I2C_ADR Register (0×0F). When
I2C interface operation is being used, RD and WR
must be tied to ground. PDAT [7:0] are available to
be used for GPIO operation in I2C host interface
mode. For 3.3 V operation it is necessary to have
the appropriate level shifting for I2C signals.
8.1.2 8-bit Parallel Interface
The CS4954/5 is equipped with a full 8-bit parallel
microprocessor write and read control port. Along
with the PDAT [7:0] pins, the control port interface
is comprised of host read (RD) and host write (WR)
active low strobes and host address enable
(ADDR), which, when low, enables unique address
register accesses. The control port is used to access
internal registers which configure the CS4954/5 for
various modes of operation. The internal registers
are uniquely addressed via an address register. The
address register is accessed during a host write cycle with the WR and ADDR pins set low. Host
write cycles with ADDR set high will write the 8bits on the PDAT [7:0] pins into the register currently selected by the address register. Likewise
read cycles occuring with RD set low and ADDR
set high will return the register contents selected by
the address register. Reference the detailed electrical timing parameter section of this data sheet for
exact host parallel interface timing characteristics
and specifications.
WR
Trec
Trec
RD
Figure 27. 8-bit Parallel Host Port Timing: Read-Write/Write-Read Cycle
Trd
RD
Trpw
Trah
PADR
PDAT[7:0]
Tas
Trda
Trdh
Figure 28. 8-bit Parallel Host Port Timing: Address Read Cycle
34
DS278F1
CS4954 CS4955
Twpw
Twr
WR
Twac
PADR
PDAT[7:0]
Tas
Twds
Twdh
Figure 29. 8-bit Parallel Host Port Timing: Address Write Cycle
8.2
Register Description
A set of internal registers are available for controlling the operation of the CS4954/5. The registers
extend from internal address 0×00 through 0×5A.
Table 9 shows a complete list of these registers and
their internal addresses. Note that this table and the
Address
0×00
0×01
0×02
0×03
0×04
0×05
0×06
0×07
0×08
0×09
0×0A
0×0B
0×0C
0×0D
0×0E
0×0F
0×10
0×11
0×12
0×13
0×14
0×15
0×16
subsequent register description section describe the
full register map for the CS4954 only. A complete
CS4955 register set description is available only to
Macrovision ACP-PPV Licensed Buyers.
8.2.1 Control Registers
Register Name
control_0
control_1
control_2
control_3
control_4
control_5
control_6
RESERVED
bkg_color
gpio_ctrl_reg
gpio_data_reg
RESERVED
RESERVED
SYNC_0
SYNC_1
I2C_ADR
SC_AMP
SC_SYNTH0
SC_SYNTH1
SC_SYNTH2
SC_SYNTH3
HUE_LSB
HUE_MSB
Type
r/w
r/w
r/w
r/w
r/w
r/w
r/w
Default value
01h
02h
00h
00h
3Fh
00h
00h
r/w
r/w
r/w
03h
00h
00h
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
90h
F4h
00h
1Ch
3Eh
F8h
E0h
43h
00h
00h
Table 9. Control Registers
DS278F1
35
CS4954 CS4955
Address
0×17
0×18
0×19
0×1A
0×1B
0×1C
0×1D
0×1E
0×1F
0×20
0×21
0×22
0×23
0×24
0×25
0×26
0×27
0×28
0×29
0×2A
0×2B
0×2C
0×2D
0×2E
0×2F
0×30
0×31
0×32
0×33
0×34
0×35 - 0×59
0×5A
0×61 - 0×7F
Register Name
SCH PHASE ADJUST
CC_EN
CC_21_1
CC_21_2
CC_284_1
CC_284_2
RESERVED
WSS_REG_0
WSS_REG_1
WSS_REG_2
RESERVED
CB_AMP
CR_AMP
Y_AMP
R_AMP
G_AMP
B_AMP
BRIGHT_OFFSET
TTXHS
TTXHD
TTXOVS
TTXOVE
TTXEVS
TTXEVE
TTX_DIS1
TTX_DIS2
TTX_DIS_3
INT_EN
INT_CLR
STATUS_0
RESERVED
STATUS_1
RESERVED
Type
r/w
r/w
r/w
r/w
r/w
r/w
Default value
00h
00h
00h
00h
00h
00h
r/w
r/w
r/w
00h
00h
00h
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
r/w
read only
80h
80h
80h
80h
80h
80h
00h
A1h
02h
00h
00h
00h
00h
00h
00h
00h
00h
00h
read only
04h
Table 9. Control Registers (Continued)
36
DS278F1
CS4954 CS4955
Control Register 0
Address
0×00
Bit Number
Bit Name
Default
7
Bit
Mnemonic
CONTROL_0
6
Read/Write
5
TV_FMT
0
0
Default Value = 01h
4
3
2
1
0
MSTR
CCIR656
PROG
IN_MODE
CBCR_UV
0
0
0
0
1
0
Function
selects the TV display format
7:5
TV_FMT
000:
NTSC-M CCIR601 timing (default)
001:
NTSC-M RS170A timing
010:
PAL-B, D, G, H, I
011:
PAL-M
100:
PAL-N (Argentina)
101:
PAL-N (non Argentina)
110-111:
reserved
1 = Master Mode, 0 = Slave Mode
4
MSTR
3
CCIR656
2
PROG
1
IN_MODE
Input select (0 = solid background, 1 = use V [7:0] data)
0
CBCR_UV
enable YCbCr to YUV conversion (1 = enable, 0 = disable)
video input is in ITU R.BT656 format (0 = off, 1 = on)
Progressive scanning enable (enable = 1)
Control Register 1
Address
Bit Number
Bit Name
Default
Bit
0×01
CONTROL_1
7
6
LUM DEL
0
0
Read/Write
Default Value = 02h
5
4
3
2
1
0
CH BW
LPF_ON
RGB_BW
FLD
PED
CBCRSEL
0
0
0
0
1
0
Mnemonic
Function
luma delay on the composite1 output
7:6
LUM DEL
00:
no delay (default)
01:
1 pixel clock delay
10:
2 pixel clock delay
11:
3 pixel clock delay
5
CH BW
chroma lpf bandwidth (0 = 650 kHz, 1 = 1.3 Mhz)
4
LPF ON
chroma lpf on/off (0 = off, 1 = on)
3
RGB_BW
0 = Full bandwidth on RGB, 1 = BW reduced to 2.5 MHz (3 dB point) (default 0)
2
FLD_POL
Polarity of Field (0: odd field = 0,1: odd field = 1)
1
PED
0
CBCRSEL
DS278F1
Pedestal offset (0: 0 IRE, 1: 7.5 IRE)
CbCr select (0 = chroma undelayed, 1 = chroma delayed by one clock)
37
CS4954 CS4955
Control Register 2
Address
Bit Number
Bit Name
Default
Bit
0×02
CONTROL_2
7
6
Read/Write
5
OUTPUT FORMAT
0
0
0
Default Value = 00h
4
3
2
1
0
TTX WST
TTX EN
SYNC_DLY
XTAL
SC_EN
0
0
0
0
0
Mnemonic
Function
selects the output through the DACs
7:5
OUTPUT FORMAT
000 :
rgb, s-video, composite1 (6 DACs) (default)
001 :
yuv, s-video, composite1 (6 DACs)
010 :
s-video, composite1, composite2, (4 DACs)
011 :
rgb, composite1, composite2 (5 DACs)
100 :
yuv, composite1, composite2 (5 DACs)
101-111:
don’t care
To select between world standard (NTSC), world standard (PAL), or north
american teletext standard during NTSC or PAL modes (1 = WST TTX) (default
is 0)
4
38
TTX WST
3
TTX EN
2
SYNC DLY
1
XTAL
0
BU DIS
In NTSC-M or PAL-M mode. This bit works in conjunction with the TV FORMAT
register.
0:
NABTS, if TV FORMAT is NTSC or PAL-M
1:
WST (NTSC), if TV FORMAT is NTSC or PAL-M
0:
Europe TTX, if TV FORMAT is PAL-B, G..., N
1:
WST (PAL), if TV FORMAT is PAL-B, G, ..., N
Enable teletext process (1 = enable)
Slave mode 1 pixel sync delay (1 = enable)
Crystal oscillator for subcarrier adjustment enable (1 = enable)
Chroma burst disable (1 = disable)
DS278F1
CS4954 CS4955
Control Register 3
0×03
Address
Bit Number
Bit Name
Default
CONTROL_3
7
6
Read/Write
5
4
RESERVED
0
0
Default Value = 00h
3
2
1
0
FD THR C1 FD THR C2 FD THR SV FD THR EN
0
0
0
0
0
CBAR
0
Bit
Mnemonic
Function
7:5
-
4
FD THR C1
feedthrough enabled for composite 1 output (0 = off, 1 = on)
3
FD THR C2
feedthrough enabled for composite 2 output (0 = off, 1 = on)
2
FD THR SV
feedthrough enabled for s-video (on luma signal) (0 = off, 1 = on)
1
FD THR_EN
Enable (1 = enable) input to feed through during inactive lines
0
CBAR
reserved
internal color bar generator (0 = off, 1 = on)
Control Register 4
Address
0×04
Bit Number
Bit Name
Default
7
CB_H_SEL
CONTROL_4
6
5
Default Value = 3Fh
4
3
CB_FLD_SEL COMDAC_PD SVIDLUM_PD SVIDCHR_PD
0
Bit
Mnemonic
7
CB_H_SEL
6
CB_FLD_SEL
5
COMDAC_PD
4
SVIDLUM_PD
3
SVIDCHR_PD
2
R_PD
1
G_PD
0
B_PD
DS278F1
Read/Write
0
1
1
1
2
1
0
R_PD
G_PD
B_PD
1
1
1
Function
Composite Blank / HSYNC output select (1 = CB select, 0 = HSYNC select)
Composite Blank / FIELD output select (1 = CB select, 0 = HSYNC select)
power down composite DAC
0: power up, 1: power down
power down luma s-video DAC
0: power up, 1: power down
power down chroma s-video DAC
0: power up, 1: power down
power down red rgb video DAC
0: power up, 1: power down
power down green rgb video DAC
0: power up, 1: power down
power down blue rgb video DAC
0: power up, 1: power down
39
CS4954 CS4955
Control Register 5
0×05
Address
CONTROL_5
Read/Write
Default Value = 00h
Bit Number
Bit Name
Default
7
6
5
4
3
2
1
0
RSVD
LOW IMP
EN COM
EN L
EN C
EN R
EN G
EN B
0
0
0
0
0
0
0
0
Bit
Mnemonic
7
-
6
LOW IMP
selects between high output impedance (0) or low output impedance (1) mode of DACs
5
EN COM
enable DAC for composite output 0: tri-state, 1: enable
4
EN L
enable s-video DAC for luma output 0: tri-state, 1: enable
3
EN C
enable s-video DAC for chroma output 0: tri-state, 1: enable
2
EN_R
enable rgb video DAC for red output 0: tri-state, 1: enable
1
EN_G
enable rgb video DAC for green output 0: tri-state, 1: enable
0
EN_B
enable rgb video DAC for blue output 0: tri-state, 1: enable
Function
reserved
Control Register 6
Address
Bit Number
Bit Name
Default
40
0×06
CONTROL_6
7
Read/Write
Default Value = 00h
6
5
4
3
656 SYNC
OUT
CLIP OFF
TTXEN
COM2
TTXEN
COM1
TTXEN
SVID
0
0
0
0
0
2
1
0
BSYNC DIS GSYNC DIS RSYNC DIS
0
0
0
Bit
Mnemonic
Function
7
656 SYNC OUT
6
CLIP OFF
5
TTXEN COM2
Enable teletext at the composit2 output (0: disable teletext, 1 : enable teletext)
4
TTXEN COM1
Enable teletext at the composit1 output ( 0: disable teletext, 1 : enable teletext)
3
TTXEN SVID
Enable teletext at the s-video output ( 0: disable teletext, 1: enable teletext)
2
BSYNC DIS
Disable syncs in the blue or v output (0: enable syncs, 1: disable syncs)
1
GSYNC DIS
Disable syncs in the green or u output ( 0: enable syncs, 1: disable syncs)
0
RSYNC DIS
Disable syncs in the red or y output (0: enable syncs, 1: disable syncs)
Enable (=1) output of hsync and vsync in the ITU R.BT656 mode
Clipping input signals disable (0: clipping active 1: no clipping)
DS278F1
CS4954 CS4955
Background Color Register
0×08
Address
Bit Number
Bit Name
Default
7
BKG_COLOR
6
Read/Write
5
Default Value = 03h
4
3
2
1
0
0
0
1
1
BG
0
Bit
Mnemonic
7:0
BG
0
0
0
Function
Background color (7:5 = R, 4:2 = G, 1:0 = B) (default is 0000 0011 - blue)
GPIO Control Register
0×09
Address
Bit Number
Bit Name
Default
7
GPIO__REG
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
GPR_CNTRL
0
Bit
Mnemonic
7:0
GPR CNTRL
0
0
0
0
Function
Input(0)/output(1) control of GPIO registers (bit 0: PDAT(0), bit 7: PDAT(7))
GPIO Data Register
0×0A
Address
Bit Number
Bit Name
Default
7
GPIO_REG
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
GPIO REG
0
0
0
0
Bit
Mnemonic
Function
7:0
GPIO REG
GPIO data register ( data is output on PDAT bus if appropriate bit in address 09 is
set to “1”, otherwise data is input/output through I2C)- This register is only accessible
in I2C mode.
Sync Register 0
Address
Bit Number
Bit Name
Default
0×0D
7
1
Mnemonic
7:3
PROG VS[4:0]
DS278F1
6
Read/Write
5
4
Default Value = 90h
3
2
PROG VS[4:0]
Bit
2:0
Sync_0
0
0
1
0
PROG HS[10:8]
1
0
0
0
0
Function
programmable vsync lines
PROG HS[10:8] programmable hsync pixels (3 most significant bits)
41
CS4954 CS4955
Sync Register 1
0×0E
Address
Sync_1
Bit Number
Bit Name
Default
7
Bit
Mnemonic
7:0
PROG HS[7:0]
Read/Write
6
5
Default Value = F4h
4
3
2
1
0
1
0
0
2
1
0
0
0
0
PROG HS[7:0]
1
1
1
1
0
Function
programmable hsync pixels lsb
I2C Address Register
Address
0×0F
I2C_ADR
Bit Number
Bit Name
7
6
Read/Write
5
Default Value = 00h
4
3
I2
RESERVED
Default
C ADR
0
0
Bit
Mnemonic
7
-
6:0
I2C
0
0
0
Function
reserved
I2C device address (programmable)
Subcarrier Amplitude Register
0×10
Address
Bit Number
Bit Name
Default
SC_AMP
7
6
Read/Write
5
Default Value = 1Ch
4
3
2
1
0
1
1
0
0
BU AMP
0
Bit
Mnemonic
7:0
BU AMP
0
0
1
Function
Color burst amplitude
Subcarrier Synthesis Register
Address
42
0×11
0×12
0×13
0×14
SC_SYNTH0
SC_SYNTH1
SC_SYNTH2
SC_SYNTH3
Read/Write
Default Value = 3Eh
F8h
E0h
43h
Register
Bits
Mnemonic
Function
SC_SYNTH0
7:0
CC 0
Subcarrier synthesis bits 7:0
SC_SYNTH1
7:0
CC 1
Subcarrier synthesis bits 15:8
SC_SYNTH2
7:0
CC 2
Subcarrier synthesis bits 23:16
SC_SYNTH3
7:0
CC 3
Subcarrier synthesis bits 31:24
DS278F1
CS4954 CS4955
Hue LSB Adjust Register
Address
0×15
Bit Number
Bit Name
Default
HUE_LSB
7
Read/Write
6
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
HUE LSB
0
Bit
Mnemonic
7:0
HUE LSB
0
0
0
Function
8 LSBs for hue phase shift
Hue MSB Adjust Register
Address
0×16
Bit Number
Bit Name
Default
HUE_MSB
7
6
Read/Write
5
Default Value = 00h
4
3
2
1
RESERVED
0
Bit
Mnemonic
7:2
-
1:0
HUE MSB
0
0
0
MSB
0
0
0
0
0
Function
reserved
2 MSBs for hue phase shift
SCH Sync Phase Adjust
Address
0×17
Bit
Mnemonic
7:0
SCH
SCH
Read/Write
Default Value = 00h
Function
Default - 00h in increments of ≈1.4 degree per bit up to 360°
Closed Caption Enable Register
Address
0×18
Bit Number
Bit Name
Default
CC_EN
Read/Write
7
6
5
0
0
0
4
3
2
0
0
RESERVED
0
Bit
Mnemonic
7:2
-
1
CC EN[1]
enable closed caption for line 284
0
CC EN[0]
enable closed caption for line 21
DS278F1
Default Value = 00h
1
0
EN_284
EN_21
0
0
Function
reserved
43
CS4954 CS4955
Closed Caption Data Register
Address
0×19
0×1A
0×1B
0×1C
Bit
Mnemonic
7:0
CC_21_1
first closed caption databyte of line 21
7:0
CC_21_2
second closed caption databyte of line 21
7:0
CC_284_1
first closed caption databyte of line 284
7:0
CC_284_2
second closed caption databyte of line 284
CC_21_1
CC_21_2
CC_284_1
CC_284_2
Read/Write
Default Value = 00h
00h
00h
00h
Function
Wide Screen Signaling Register 0
Address
Bit Number
Bit Name
Default
44
0×1E
WSS_REG_0
Read/Write
Default Value = 00h
7
6
5
4
3
2
1
0
WSS_23
WSS_22
WSS_21
WSS_20
WSS_19
WSS_18
WSS_17
WSS_16
0
0
0
0
0
0
0
0
Bit
Mnemonic
Function
7
WSS_23
6
WSS_22
5
WSS_21
PAL: group 4, bit 13, NTSC: don’t care
4
WSS_20
PAL: group 4, bit 12, NTSC: don’t care
3
WSS_19
PAL: group 4, bit 11, NTSC: bit 20
2
WSS_18
PAL: group 3, bit 10, NTSC: bit 19
1
WSS_17
PAL: group 3, bit 9, NTSC: bit 18
0
WSS_16
PAL: group 3, bit 8, NTSC: bit 17
Enable wide screen signalling (enable =1)
PAL: enable WSS (enable = 1) on line 23 of field 2,
NTSC: don’t care
DS278F1
CS4954 CS4955
Wide Screen Signalling Register 1
0×1F
Address
Bit Number
Bit Name
Default
WSS_REG_1
Read/Write
Default Value = 00h
7
6
5
4
3
2
1
0
WSS_15
WSS_14
WSS_13
WSS_12
WSS_11
WSS_10
WSS_9
WSS_8
0
0
0
0
0
0
0
0
Bit
Mnemonic
Function
7
WSS_15
PAL: group 2, bit 7, NTSC: bit 16
6
WSS_14
PAL: group 2, bit 6, NTSC: bit 15
5
WSS_13
PAL: group 2, bit 5, NTSC: bit 14
4
WSS_12
PAL: group 2, bit 4, NTSC: bit 13
3
WSS_11
PAL: group 1, bit 3, NTSC: bit 12
2
WSS_10
PAL: group 1, bit 2, NTSC: bit 11
1
WSS_9
PAL: group 1, bit 1, NTSC: bit 10
0
WSS_8
PAL: group 1, bit 0, NTSC: bit 9
Wide Screen Signalling Register 2
0×20
Address
Bit Number
Bit Name
Default
WSS_REG_2
Read/Write
Default Value = 00h
7
6
5
4
3
2
1
0
WSS_7
WSS_6
WSS_5
WSS_4
WSS_3
WSS_2
WSS_1
WSS_0
0
0
0
0
0
0
0
0
Bit
Mnemonic
Function
7
WSS_7
PAL: don’t care, NTSC: bit 8
6
WSS_6
PAL: don’t care, NTSC: bit 7
5
WSS_5
PAL: don’t care, NTSC: bit 6
4
WSS_4
PAL: don’t care, NTSC: bit 5
3
WSS_3
PAL: don’t care, NTSC: bit 4
2
WSS_2
PAL: don’t care, NTSC: bit 3
1
WSS_1
PAL: don’t care, NTSC: bit 2
0
WSS_0
PAL: don’t care, NTSC: bit 1
Filter Register 0
Address
Bit Number
Bit Name
Default
0×22
Read/Write
7
6
5
4
1
0
0
0
Default Value = 80h
3
2
1
0
0
0
0
0
U_AMP
Bit
Mnemonic
7:0
U_AMP
DS278F1
CB_AMP
Function
U(Cb) amplitude coefficient
45
CS4954 CS4955
Filter Register 1
0×23
Address
Bit Number
Bit Name
Default
7
CR_AMP
6
Read/Write
5
Default Value = 80h
4
3
2
1
0
0
0
0
0
V_AMP
1
Bit
Mnemonic
7:0
V_AMP
0
0
0
Function
V(Cr) amplitude coefficient
Filter Register 2
0×24
Address
Bit Number
Bit Name
Default
7
Y_AMP
6
Read/Write
5
Default Value = 80h
4
3
2
1
0
0
0
0
0
Y_AMP
1
Bit
Mnemonic
7:0
Y_AMP
0
0
0
Function
Luma amplitude coefficient
Filter Register 3
0×25
Address
Bit Number
Bit Name
Default
7
R_AMP
6
Read/Write
5
Default Value = 80h
4
3
2
1
0
0
0
0
0
R_AMP
1
Bit
Mnemonic
7:0
R_AMP
0
0
0
Function
Red amplitude coefficient
Filter Register 4
Address
Bit Number
Bit Name
Default
46
0×26
7
G_AMP
6
Read/Write
5
Default Value = 80h
4
3
2
1
0
0
0
0
0
G_AMP
1
Bit
Mnemonic
7:0
G_AMP
0
0
0
Function
Green amplitude coefficient
DS278F1
CS4954 CS4955
Filter Register 5
0×27
Address
Bit Number
Bit Name
Default
7
B_AMP
6
Read/Write
5
Default Value = 80h
4
3
2
1
0
0
0
0
0
2
1
0
0
0
0
B_AMP
1
Bit
Mnemonic
7:0
B_AMP
0
0
0
Function
Blue amplitude coefficient
Filter Register 6
0×28
Address
Bit Number
Bit Name
Default
7
Bright_Offsett
6
Read/Write
5
Default Value = 00h
4
3
BRIGHTNESS_OFFSET
0
Bit
Mnemonic
7:0
BRGHT_OFFSET
0
0
0
0
Function
Brightness adjustment ( range: -128 to +127)
Teletext Register 0
0×29
Address
Bit Number
Bit Name
Default
7
TTXHS
6
Read/Write
5
Default Value = A1h
4
3
2
1
0
0
0
0
1
TTXHS
1
Bit
Mnemonic
7:0
TTXHS
0
1
0
Function
Start of teletext request pulses or start of window
Teletext Register 1
Address
Bit Number
Bit Name
Default
Bit
7:0
0×2A
7
TTXHD
6
Read/Write
5
Default Value = 02h
4
3
2
1
0
0
0
1
0
TTXHD
0
Mnemonic
TTXHD
0
0
0
Function
If TTX_WINDOW = 0 then this register is used as the Pipeline delay between
TTXRQ and TTXDAT signal in the teletext source. User programmable delay step
of 37 ns per LSB.
If TTX_WINDOW = 1 then this register is used as the 8 LSBs of the teletext insertion
windows; the 3 MSBs are located in register 0×31. (register 0×31 bit 3)
DS278F1
47
CS4954 CS4955
Teletext Register 2
0×2B
Address
Bit Number
Bit Name
Default
7
TTXOVS
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
TTXOVS
0
Bit
Mnemonic
7:0
TTXOVS
0
0
0
Function
Start of teletext line window in odd field
Teletext Register 3
0×2C
Address
Bit Number
Bit Name
Default
7
TTXOVE
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
TTXOVE
0
Bit
Mnemonic
7:0
TTXOVE
0
0
0
Function
End of teletext line window in odd field
Teletext Register 4
0×2D
Address
Bit Number
Bit Name
Default
7
TTXEVS
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
TTXEVS
0
Bit
Mnemonic
7:0
TTXEVS
0
0
0
Function
Start of teletext line window in even field
Teletext Register 5
Address
Bit Number
Bit Name
Default
48
0×2E
7
TTXEVE
6
Read/Write
5
Default Value = 00h
4
3
2
1
0
0
0
0
0
TTXEVE
0
Bit
Mnemonic
7:0
TTXEVE
0
0
0
Function
End of teletext line window in even field
DS278F1
CS4954 CS4955
Teletext Register 6
0×2F
Address
Bit Number
Bit Name
Default
Bit
7:0
7
TTX_DIS1
Read/Write
6
5
Default Value = 00h
4
3
2
1
0
0
0
0
TTX_LINE_DIS1
0
0
0
0
Mnemonic
0
Function
Teletext disable bits corresponding to the lines 5-12 respectively, (11111111=all
TTX_LINE_DIS1 eight lines are disabled),
(MSB is for line 5, LSB is for line 12)
Teletext Register 7
0×30
Address
Bit Number
Bit Name
Default
Bit
7:0
TTX_DIS2
Read/Write
7
6
5
0
0
0
Default Value = 00h
4
3
2
1
0
0
0
0
TTX_LINE_DIS2
0
Mnemonic
0
Function
Teletext disable bits corresponding to the lines 13-20 respectively, (11111111=all
TTX_LINE_DIS2 eight lines are disablled,
(MSB is for line 13, LSB is for line 20)
Teletext Register 8
Address
Bit Number
Bit Name
Default
0×31
7
TTX_DIS3
6
Read/Write
5
TTXHD
0
0
Default Value = 00h
4
3
2
RESERVED TTX_WINDOW
0
0
0
1
0
TTX_LINE_DIS3
0
0
0
Bit
Mnemonic
Function
7:5
TTXHD
If TTX_WINDOW = 0 these 3 bits are unused.
If TTX_WINDOW = 1 these 3 bits are the MSBs of the register 0×2A; they are used
to specify the length of the teletext insertion window
4
Reserved
3
TTX_WINDOW
Selects between TTXRQ (= 0) pulsation or TTXRQ ( =1) Window mode
2:0
TTX_LINE_DIS3
Teletext disable bits corresponding to the lines 13-20 respectively, (111=all three
lines are disabled),
(MSB is for line 21, LSB is for line 23)
DS278F1
49
CS4954 CS4955
Interrupt Register 0
0×32
Address
Bit Number
Bit Name
Default
INT_EN
7
6
0
0
Read/Write
5
Default Value = 00h
4
3
0
0
RESERVED
0
Bit
Mnemonic
7:3
-
2
INT_21_EN
interrupt enable for closed caption line 21
1
INT_284_EN
interrupt enable for closed caption line 284
0
INT_V_EN
2
1
0
INT_21_EN
INT_284_EN
INT_V_EN
0
0
0
Function
reserved
interrupt enable for new video field
Interrupt Register 1
0×33
Address
INT_CLR
Bit Number
Bit Name
Default
7
6
Read/Write
5
Default Value = 00h
4
3
RESERVED
0
Bit
Mnemonic
7:3
-
0
0
0
2
1
0
CLR_INT_21
CLR_INT_284
CLR_INT_V
0
0
0
0
Function
reserved
2
CLR_INT_21
clear interrupt for closed caption line 21 (INT 21)
1
CLR_INT_284
clear interrupt for closed caption line 284 (INT_284)
0
CLR_INT_V
clear interrupt for new video field (INT_V)
Status Register 0
0×34
Address
Bit Number
Bit Name
Default
STATUS_0
Read Only
Default Value = 00h
5
4
3
2:0
INT_21
INT_284
INT_V
FLD
0
0
0
0
Bit
Mnemonic
Function
5
INT_21
Interrupt flag for line 21 (closed caption) complete
4
INT_284
Interrupt flag for line 284 (closed caption) complete
3
INT_V
2:0
FLD_ST
Interrupt flag for video field change
Field Status bits(001 = field 1,000 = field 8)
Status Register 1
Address
Bit Number
Bit Name
Default
50
0×5A
STATUS_1
Read only
Default Value = 04h
7
6
5
4
0
0
0
0
3
2
1
0
0
1
0
0
DEVICE_ID
Bit
Mnemonic
7:0
DEVICE_ID
Function
Device identification: CS4954: 0000 0100, CS4955: 0000 0101
DS278F1
CS4954 CS4955
9.
BOARD DESIGN AND LAYOUT
CONSIDERATIONS
The printed circuit layout should be optimized for
lowest noise on the CS4954/5 placed as close to the
output connectors as possible. All analog supply
traces should be as short as possible to minimize inductive ringing.
A well designed power distribution network is essential in eliminating digital switching noise. The
ground planes must provide a low-impedance return path for the digital circuits. A PC board with a
minimun of four layers is recommended. The
ground layer should be used as a shield to isolate
noise from the analog traces. The top layer (1)
should be reserved for analog traces but digital
traces can share this layer if the digital signals have
low edge rates and switch little current or if they are
separated from the analog traces by a signigicant
distance (dependent on their frequency content and
current). The second layer should then be the
ground plane followed by the analog power plane
on layer three and the digital signal layer on layer
four.
9.1
Power and Ground Planes
The power and ground planes need isolation gaps
of at least 0.05" to minimize digital switching noise
effects on the analog signals and components. A
split analog/digital ground plane should be connected at one point as close as possible to the
CS4954/5.
9.2
Power Supply Decoupling
Start by reducing power supply ripple and wiring
harness inductance by placing a large (33-100 uF)
capacitor as close to the power entry point as possible. Use separate power planes or traces for the
digital and analog sections even if they use the
same supply. If necessary, further isolate the digital
and analog power supplies by using ferrite beads on
each supply branch followed by a low ESR capacitor.
DS278F1
Place all decoupling caps as close as possible the
the device as possible. Surface mount capacitors
generally have lower inductance than radial lead or
axial lead components. Surface mount caps should
be place on the component side of the PCB to minimize inductance caused by board vias. Any vias,
especially to ground, should be as large as possible
to reduce their inductive effects.
9.3
Digital Interconnect
The digital inputs and outputs of the CS4954/5
should be isolated from the analog outputs as much
as possible. Use separate signal layers whenever
possible and do not route digital signals over the
analog power and ground planes.
Noise from the digital section is related to the digital edge rates used. Ringing, overshoot, undershoot, and ground bounce are all related to edge
rate. Use lower speed logic such as HCMOS for the
host port interface to reduce switching noise. For
the video input ports, higher speed logic is required, but use the slowest practical edge rate to reduce noise. To reduce noise, it is important to
match the source impedance, line impedance, and
load impedance as much as possible. Generally, if
the line length is greater than one fourth the signal
edge rate, line termination is necessary. Ringing
can also be reduced by damping the line with a series resistor (22-150 Ω). Under extreme cases, it
may be advisable to use microstrip techniques to
further reduce radiated switching noise if very fast
edge rates (<2ns) are used. If microstrip techniques
are used, split the analog and digital ground planes
and use proper RF decoupling techniques.
9.4
Analog Interconnect
The CS4954/5 should be located as close as possible the output connectors to minimize noise pickup
and reflections due to impedance mismatch. All unused analog outputs should be placed in shutdown.
This reduces the total power that the CS4954/5 requires, and eliminates the impedance mismatch
51
CS4954 CS4955
presented by an unused connector. The analog outputs should not overlay the analog power plane to
maximize high frequency power supply rejection.
idea to use output filters that are AC coupled to
avoid any problems.
9.5
All MOS devices are sensitive to Electro Static
Discharge (ESD). When manipulating these devices, proper ESD precautions are recommended to
avoid performance degradation or permanent dramage.
Analog Output Protection
To minimize the possibility of damage to the analog output sections, make sure that all video connectors are well grounded. The connector should
have a good DC ground path to the analog and digital power supply grounds. If no DC (and low frequency) path is present, improperly grounded
equipment can impose damaging reverse currents
on the video out lines. Therefore, it is also a good
9.6
9.7
ESD Protection
External DAC Output Filter
If an output filter is required, the low pass filter
shown in Figure 30 can be used.
NOTE:
C2 should be chosen so that C1 = C2 + Ccable
2.2µH
IN
OUT
C1
33 0 pF
C2
2 2 0p F
Figure 30. External Low Pass Filter
52
DS278F1
CS4954 CS4955
L1
Ferrite Bead
Vcc
4.7 µF
0.1 µF
17
15
14
NC
16
VDD
XTALIN
36 41 46
VAA
VREF 38
XTALOUT
PADDR
75 or
300 Ω
RED 39
30
TTXDAT
31
Gpio port
26-19
27
Vcc
28
1.5 kΩ
GREEN
TTXRQ
75 or
300 Ω
PDAT[7:0]
BLUE 43
RD
WR
I
33
Composite Video
Connector
75 or 30 0Ω
CS4954
CS4955
SDA
2C
to SCART
Connector
75 or
300 Ω
CVBS 44
1.5 kΩ
110 Ω
32
Controller
40
Y
48
75 or 300 Ω
SCL
110 Ω
27 MHz Clock
29
Pixel Data
8
S-Video
Connector
CLK
C 47
V[7:0]
8-1
9
10
11
75 or 30 0Ω
FIELD /CB
HSYNC /CB
VSYNC
13 TEST
GNDD
18
INT
12
INT 34
RESET
37
ISET
GNDA
34 42 45
4 kΩ±1%
Figure 31. Typical Connection Diagram
DS278F1
53
CS4954 CS4955
10. PIN DESCRIPTION
B
CVBS
GNDA
VAA
C
Y
V0
V1
V2
V3
V4
V5
V6
V7
FIELD /CB
HSYNC/CB
VSYNC
INT
TEST
XTAL_OUT
XTAL_IN
PADR
VDD
GNDD
54
48 47 46 45 44 43 42 41 40 39 38 37
1
36
2
35
3
34
4
5
6
7
8
33
CS4954-CQ
CS4955-CQ
48-Pin TQFP
Top View
32
31
30
29
9
28
10
27
11
26
12
25
13 14 15 16 17 18 19 20 21 22 23 24
GNDA
VAA
G
R
VREF
ISET
VAA
GNDA
RESET
SCL
SDA
TTXRQ
TTXDAT
CLKIN
WR
RD
PDAT0
PDAT1
PDAT2
PDAT3
PDAT4
PDAT5
PDAT6
PDAT7
DS278F1
CS4954 CS4955
Pin Name
V [7:0]
CLK
PADDR
XTAL_IN
XTAL_OUT
HSYNC/CB
VSYNC
FIELD/CB
RD
WR
PDAT [7:0]
SDA
SCL
CVBS
Y
C
R
G
B
VREF
ISET
TTXDAT
TTXRQ
INT
RESET
TEST
VAA
GNDD
VDD
GNDA
Pin Number
8, 7, 6, 5, 4, 3, 2, 1
29
16
15
14
10
Type
IN
IN
IN
IN
OUT
I/O
Description
Digital video data inputs
27 MHz input clock
Address enable line
subcarrier crystal input
subcarrier crystal output
Active low horizontal sync, or composite blank signal
11
9
27
I/O
OUT
IN
Active low vertical sync.
Video field ID. Selectable polarity or composite blank
Host parallel port read strobe, active low
28
IN
19, 20, 21, 22, 23, 24, 25, 26
32
33
44
48
47
39
40
43
38
I/O
I/O
IN
CURRENT
CURRENT
CURRENT
CURRENT
CURRENT
CURRENT
I/O
37
30
31
12
34
CURRENT
IN
OUT
OUT
IN
Host parallel port/ general purpose I/O
I2C data
I2C clock input
Composite video output
Luminance analog output
Chrominance analog output
Red analog output
Green analog output
Blue analog output
Internal voltage reference output or external reference input
DAC current set
Teletext data input
Teletext request output
Interrupt output, active high
Active low master RESET
13
36, 41, 46
18
17
35, 42, 45
IN
PS
PS
PS
PS
TEST pin. Ground for normal operation
+ 5 V or + 3.3 V supply (must be same as VDD)
Ground
+5 V or 3.3 V supply (must be same as VAA)
Ground
Host parallel port write strobe, active low
Table 10. Device Pin Description s
DS278F1
55
CS4954 CS4955
11. PACKAGE DRAWING
48L TQFP PACKAGE DRAWING
E
E1
D D1
1
e
B
∝
A
A1
L
INCHES
MIN
--0.002
0.007
0.343
0.272
0.343
0.272
0.016
0.018
0.000°
∝
* Nominal pin pitch is 0.50 mm
DIM
A
A1
B
D
D1
E
E1
e*
L
MAX
0.063
0.006
0.011
0.366
0.280
0.366
0.280
0.024
0.030
7.000°
MILLIMETERS
MIN
MAX
--1.60
0.05
0.15
0.17
0.27
8.70
9.30
6.90
7.10
8.70
9.30
6.90
7.10
0.40
0.60
0.45
0.75
0.00°
7.00°
Controlling dimension is mm.
JEDEC Designation: MS026
56
DS278F1
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