Texas Instruments | Microprocessor-Compatible 12-Bit D/A Converter | Datasheet | Texas Instruments Microprocessor-Compatible 12-Bit D/A Converter Datasheet

Texas Instruments Microprocessor-Compatible 12-Bit D/A Converter Datasheet
DAC813
®
DAC
813
DAC
813
Microprocessor-Compatible
12-BIT DIGITAL-TO-ANALOG CONVERTER
FEATURES
converter with voltage output operational amplifier.
Fast current switches and laser-trimmed thin-film
resistors provide a highly accurate, fast D/A converter.
● ±1/2LSB NONLINEARITY OVER
TEMPERATURE
● GUARANTEED MONOTONIC OVER
TEMPERATURE
Digital interfacing is facilitated by a double buffered
latch. The input latch consists of one 8-bit byte and
one 4-bit nibble to allow interfacing to 8-bit (right
justified format) or 16-bit data buses. Input gating
logic is designed so that the last nibble or byte to be
loaded can be loaded simultaneously with the transfer
of data to the D/A latch saving computer instructions.
● LOW POWER: 270mW typ
● DIGITAL INTERFACE DOUBLE
BUFFERED: 12 AND 8 + 4 BITS
● SPECIFIED AT ±12V AND ±15V POWER
SUPPLIES
● RESET FUNCTION TO BIPOLAR ZERO
● 0.3" WIDE DIP AND SO PACKAGES
A reset control allows the DAC813 D/A latch to
asynchronously reset the D/A output to bipolar zero,
a feature useful for power-up reset, recalibration, or
for system re-initialization upon system failure.
DESCRIPTION
The DAC813 is specified to ±1/2LSB maximum linearity error (J, A grades) and ±1/4LSB (K grade).
It is packaged in 28-pin 0.3" wide plastic DIP and
28-lead plastic SOIC
The DAC813 is a complete monolithic 12-bit digitalto-analog converter with a flexible digital interface.
It includes a precision +10V reference, interface control logic, double-buffered latch and a 12-bit D/A
Reset
4 MSBs
8 LSBs
Input Latch
Input Latch
4
8
BPO
24.9kΩ
20V Span
25kΩ
D/A Latch
20V Span
12
10V
Reference
49.5kΩ
VREF OUT
12-Bit D/A
Converter
25kΩ
VOUT
VREF IN
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
Internet: http://www.burr-brown.com/ • FAXLine: (800) 548-6133 (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
®
© 1990 Burr-Brown Corporation
SBAS004
PDS-1077G
1
DAC813
Printed in U.S.A. March, 1998
SPECIFICATIONS
At TA = +25°C, ±VCC = ±12V or ±15V and load on VOUT = 5kΩ || 500pF to common, unless otherwise noted.
DAC813JP, JU, AU
PARAMETER
CONDITIONS
DIGITAL INPUTS
Resolution
Codes(1)
Digital Inputs Over Temperature Range(2)
VIH(3)
VIL
DATA Bits, WR, Reset, LDAC, LMSB, LLSB
IIH
IIL
ACCURACY
Linearity Error
Differential Linearity Error
Gain Error(4)
Unipolar Offset Error(5)
Bipolar Zero Error(6)
Monotonicity
Power Supply Sensitivity: +VCC
–VCC
DRIFT
Gain
Unipolar Offset
Bipolar Zero
Linearity Error Over Temperature Range
Monotonicity Over Temperature Range
SETTLING TIME(8) (To Within ±0.01% of
FSR of Final Value; 5kΩ || 500pF load)
For Full Scale Range Change
MIN
TEMPERATURE RANGE
Specification: J, K
A
Operating: J, K
A
Storage: J, K
A
MIN
TYP
MAX
UNITS
✻
Bits
✻
✻
✻
✻
VDC
VDC
µA
µA
±1/8
±1/4
✻
✻
✻
✻
✻
✻
±1/4
±1/2
✻
✻
✻
LSB
LSB
%
% of FSR(7)
% of FSR
✻
✻
ppm of FSR/%
ppm of FSR/%
12
+2
0
✻
+5.5
+0.8
±10
±10
VIN = +2.7V
VIN = +0.4V
✻
✻
±1/4
±1/2
±0.05
±0.01
±0.02
Guaranteed
5
1
±1/2
±3/4
±0.2
±0.02
±0.2
±5
±1
±3
±1/2
Guaranteed
±30
±3
±10
±3/4
✻
✻
✻
±1/4
✻
±15
±3
±5
±1/2
ppm/°C
ppm of FSR/°C
ppm of FSR/°C
LSB
20V Range
10V Range
4.5
3.3
2
10
6
5
✻
✻
✻
✻
✻
✻
µs
µs
µs
V/µs
±VCC > ±11.4V
±VCC > ±11.4V
0 to +10
±5, ±10
20V Range
Over Specification
Temperature Range
±5
10
10
✻
✻
V
V
mA
Ω
✻
At DC
REFERENCE VOLTAGE
Voltage
Source Current Available for External Loads
Impedance
Temperature Coefficient
Short Circuit to Common Duration
POWER SUPPLY REQUIREMENTS
Voltage: +VCC
–VCC
Current: +VCC + VL
–VCC
Potential at DCOM with Respect to ACOM(10)
Power Dissipation
MAX
USB, BOB
For 1LSB Change at Major Carry(9)
Slew Rate
ANALOG OUTPUT
Voltage Range: Unipolar
Bipolar
Output Current
Output Impedance
Short Circuit to Common Duration
TYP
DAC813KP, KU
✻
✻
0.2
Indefinite
+9.95
5
+11.4
–11.4
No Load
No Load
+10
+10.05
2
±5
Indefinite
±25
+15
–15
13
–5
–3
270
0
–40
–40
–55
–60
–65
+16.5
–16.5
15
–7
+3
330
+70
+85
+85
+125
+100
+150
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
V
mA
Ω
ppm/°C
✻
✻
✻
✻
✻
✻
VDC
VDC
mA
mA
V
mW
✻
✻
✻
✻
✻
✻
°C
°C
°C
°C
°C
°C
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻
✻ Same as specification for DAC813AU, JP, JU.
NOTES: (1) USB = Unipolar Straight Binary; BOB = Bipolar Offset Binary. (2) TTL and 5V CMOS compatible. (3) Open DATA input lines will be pulled above +5.5V.
See discussion under LOGIC INPUT COMPATIBILITY in the OPERATION section. (4) Specified with 500Ω Pin 6 to 7. Adjustable to zero with external trim
potentiometer. (5) Error at input code 000HEX for unipolar mode, FSR = 10V. (6) Error at input code 800HEX for bipolar range. Specified with 100Ω Pin 6 to 4 and
with 500Ω pin 6 to 7. See page 9 for zero adjustment procedure. (7) FSR means Full Scale Range and is 20V for the ±10V range. (8) Maximum represents the
3σ limit. Not 100% tested for this parameter. (9) At the major carry, 7FFHEX to 800HEX and 800HEX to 7FFHEX. (10) The maximum voltage at which ACOM and DCOM
may be separated without affecting accuracy specifications.
®
DAC813
2
ABSOLUTE MAXIMUM RATINGS(1)
PIN DESCRIPTIONS
PIN
1
2, 3
4
NAME
DESCRIPTION
+VL
Positive supply pin for logic circuits. Connect to +VCC.
20V Range
Connect Pin 2 or Pin 3 to Pin 9 (VOUT) for a 20V
FSR. Connect both to Pin 9 for a 10V FSR.
BPO
Bipolar offset. Connect to Pin 6 (VREF OUT) through
100Ω resistor or 200Ω potentiometer for bipolar
operation.
5
ACOM
Analog common, ±VCC supply return.
6
VREF OUT
+10V reference output referred to ACOM.
7
VREF IN
Connected to VREF OUT through a 1kΩ gain
adjustment potentiometer or a 500Ω resistor.
8
+VCC
Analog supply input, nominally +12V to +15V
referred to ACOM.
+VCC to ACOM .......................................................................... 0 to +18V
–VCC to ACOM .......................................................................... 0 to –18V
+VCC to –VCC ............................................................................ 0 to +36V
DCOM with respect to ACOM ............................................................. ±4V
Digital Inputs (Pins 11–15, 17–28) to DCOM .................... –0.5V to +VCC
External Voltage Applied to BPO Span Resistor .............................. ±VCC
VREF OUT ........................................................... Indefinite Short to ACOM
VOUT ................................................................. Indefinite Short to ACOM
Power Dissipation .......................................................................... 750mW
Lead Temperature (soldering, 10s) ............................................... +300°C
Max Junction Temperature ............................................................ +165°C
Thermal Resistance, θJ-A:Plastic DIP and SOIC ........................ 130°C/W
Ceramic DIP ......................................... 85°C/W
NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.
9
VOUT
D/A converter voltage output.
10
–VCC
Analog supply input, nominally –12V or –15V
referred to ACOM.
11
WR
Master enable for LDAC, LLSB, and LMSB. Must
be low for data transfer to any latch.
12
LDAC
Load DAC. Must be low with WR for data transfer
to the D/A latch and simultaneous update of the
D/A converter.
13
Reset
When low, resets the D/A latch such that a Bipolar
Zero output is produced. This control overrides all
other data input operations.
14
LMSB
Enable for 4-bit input latch of D8-D11 data inputs.
NOTE: This logic path is slower than the WR path.
15
LLSB
Enable for 8-bit input latch of D0-D7 data inputs.
NOTE: This logic path is slower than the WR path.
16
DCOM
Digital common.
17
D0
Data Bit 1, LSB.
18
D1
Data Bit 2.
19
D2
Data Bit 3.
20
D3
Data Bit 4.
21
D4
Data Bit 5.
22
D5
Data Bit 6.
23
D6
Data Bit 7.
24
D7
Data Bit 8.
25
D8
Data Bit 9.
26
D9
Data Bit 10.
27
28
D10
D11
Data Bit 11.
Data Bit 12, MSB, positive true.
ELECTROSTATIC
DISCHARGE SENSITIVITY
Electrostatic discharge can cause damage ranging from performance degradation to complete device failure. BurrBrown Corporation recommends that all integrated circuits
be handled and stored using appropriate ESD protection
methods.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits
may be more susceptible to damage because very small
parametric changes could cause the device not to meet
published specifications.
PACKAGE/ORDERING INFORMATION
PRODUCT
PACKAGE
PACKAGE
DRAWING
NUMBER(1)
DAC813JP
DAC813JU
DAC813KP
DAC813KU
DAC813AU
28-Pin Plastic DIP
28-Lead Plastic SOIC
28-Pin Plastic DIP
28-Lead Plastic SOIC
28-Lead Plastic SOIC
246
217
246
217
217
TEMPERATURE
RANGE
LINEARITY
ERROR, MAX
AT +25°C (LSB)
GAIN
DRIFT
(ppm/°C)
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
±1/2
±1/2
±1/4
±1/4
±1/2
±30
±30
±15
±15
±30
NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.
®
3
DAC813
MINIMUM TIMING DIAGRAMS
WRITE CYCLE #1
(Load first rank from Data Bus: LDAC = 1)
> 50ns
LLSB, LMSB
> 50ns
DB11–DB0
>5ns
WR
> 50ns
WRITE CYCLE #2
(Load second rank from first rank: LLSB, LMSB = 1)
> 50ns
LDAC
> 50ns
WR
tSETTLING
±1/2LSB
RESET COMMAND (Bipolar Mode)
LLSB, LMSB, LDAC, WR = Don’t Care
Reset
+10V
> 50ns
VOUT
tSETTLING
0V
±1/2LSB
–10V
®
DAC813
4
TYPICAL PERFORMANCE CURVES
POWER SUPPLY REJECTION vs
POWER SUPPLY RIPPLE FREQUENCY
DIGITAL INPUT CURRENT
vs INPUT VOLTAGE
1k
4
LLSB, WR
+VCC
100
2
Input Current (µA)
10
–VCC
1
LMSB, LDAC
0.1
10
100
1k
10k
100k
0
Reset
–2
Data
–4
1M
–2
0
2
Frequency (Hz)
CHANGE OF GAIN AND OFFSET ERROR
vs TEMPERATURE
0.8
0
Unipolar
Offset
Gain Error
–0.5
–0.4
–1
Linearity Error (LSB)
∆ Gain Error (%)
0.4
0
0
–0.8
–20
20
60
Temperature (°C)
100
–0.5
000
140
400
800
C00
FFF
Input Code (Hexidecimal)
MAJOR CARRY GLITCH
± FULL SCALE OUTPUT SWING
15
250
200
VOUT
10
150
WR
+5
0
0
100
VOUT (mV)
5
WR (V)
VOUT (V)
8
0.5
∆ Bipolar/Unipolar Offset (%)
(For 10V FSR; Double for 20V FSR)
Bipolar
Offset
–60
6
INTEGRAL LINEARITY ERROR
1
0.5
4
Input Voltage (V)
–5
50
0
Data =
7FFH
Data = 800H
WR (V)
[Change in FSR]/[Change in Supply Voltage]
(ppm of FSR/ %)
At TA = +25°C, VCC = ±15V, unless otherwise noted.
Data = 7FFH
+10
0
–10
–15
0
5
10
15
20
25
–2
Time (µs)
0
2
4
6
8
10
12
14
Time (µs)
®
5
DAC813
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C, VCC = ±15V, unless otherwise noted.
SETTLING TIME, +10V TO –10V
SETTLING TIME, –10V TO +10V
20
VOUT
20
1LSB = 4.88mV
1LSB = 4.88mV
0
WR
–10
+5
0
–20
–2
0
2
4
6
8
10
0
VOUT
–10
WR
–20
–40
12
–2
0
2
6
8
10
12
14
MONOTONICITY
A D/A converter is monotonic if the output either increases
or remains the same for increasing digital inputs. All grades
of DAC813 are monotonic over their specification temperature range.
INPUT CODES
The DAC813 accepts positive-true binary input codes.
DAC813 may be connected by the user for any one of the
following codes: USB (Unipolar Straight Binary), BOB
(Bipolar Offset Binary) or, using an external inverter on the
MSB line, BTC (Binary Two’s Complement). See Table I.
DRIFT
Gain Drift is a measure of the change in the Full Scale Range
(FSR) output over the specification temperature range. Gain
Drift is expressed in parts per million per degree Celsius
(ppm/°C).
ANALOG OUTPUT
FFFHEX
800HEX
7FFHEX
000HEX
4
Time (µs)
DISCUSSION OF
SPECIFICATIONS
MSB to LSB
0
VOUT
Time (µs)
DIGITAL
INPUT
+5
WR (V)
∆ Around +10V (mV)
10
WR (V)
∆ Around –10V (mV)
10
USB
Unipolar
Straight
Binary
BOB
Bipolar
Offset
Binary
BTC*
Binary
Two’s
Complement
+ Full Scale
+ 1/2 Full Scale
+ 1/2 Full Scale – 1LSB
Zero
+ Full Scale
Zero
Zero – 1LSB
– Full Scale
Zero – 1LSB
– Full Scale
+ Full Scale
Zero
Unipolar Offset Drift is measured with a data input of
000HEX. The D/A is configured for unipolar output. Unipolar
Offset Drift is expressed in parts per million of Full Scale
Range per degree Celsius (ppm of FSR/°C).
Bipolar Zero Drift is measured with a data input of 800HEX.
The D/A is configured for bipolar output. Bipolar Zero Drift
is expressed in parts per million of Full Scale Range per
degree Celsius (ppm of FSR/°C).
* Invert MSB of BOB code with external inverter to obtain BTC code.
TABLE I. Digital Input Codes.
SETTLING TIME
LINEARITY ERROR
Linearity error as used in D/A converter specifications by
Burr-Brown is the deviation of the analog output from a
straight line drawn between the end points (inputs all “1s”
and all “0s”). The DAC813 linearity error is specified at
±1/4LSB (max) at +25°C K grades, and ±1/2LSB (max) for
J grades.
Settling Time is the total time (including slew time) for the
output to settle within an error band around its final value
after a change in input. Three settling times are specified to
±0.012% of Full Scale Range (FSR): two for maximum full
scale range changes of 20V and 10V, and one for a 1LSB
change. The 1LSB change is measured at the major carry
(7FFHEX to 800HEX and 800HEX to 7FFHEX), the input transition at which worst-case settling time occurs.
DIFFERENTIAL LINEARITY ERROR
REFERENCE SUPPLY
Differential linearity error (DLE) is the deviation from a
1LSB output change from one adjacent state to the next. A
DLE specification of 1/2LSB means that the output step size
can range from 1/2LSB to 3/2LSB when the input changes
from one state to the next. Monotonicity requires that DLE
be less than 1LSB over the temperature range of interest.
DAC813 contains an on-chip +10V reference. This voltage
(pin 6) has a tolerance of ±50mV. VREF OUT must be connected to VREF IN through a gain adjust resistor with a
nominal value of 500Ω. The connection can be made through
an optional 1kΩ trim resistor to provide adjustment to zero
®
DAC813
6
gain error. The reference output may be used to drive
external loads, sourcing at least 5mA. This current should be
constant, otherwise the gain of the converter will vary.
WR
POWER SUPPLY SENSITIVITY
Power supply sensitivity is a measure of the effect of a
power supply change on the D/A converter output. It is
defined as a ppm of FSR output change per percent of
change in either +VCC or –VCC about the nominal voltages
expressed in ppm of FSR/%. The first performance curve on
page 5 shows typical power supply rejection versus power
supply ripple frequency.
WR
11
LMSB
14
26
25
24
23
OPERATION
No operation
D/A latch set to 800HEX
Enables 4 MSBs input latch
Enables 8 LSBs input latch
Loads D/A latch from input latches
Makes all latches transparent
The DAC813 digital inputs are TTL, 5V CMOS compatible over the operating range of +VCC. The input switching
threshold remains at the TTL threshold over the supply
range. An equivalent circuit of a digital input is shown in
Figure 2.
The logic input current over temperature is low enough to
permit driving the DAC813 directly from the outputs of 5V
CMOS devices.
All latches are level-triggered. Data present when the control signals are logic “0” will enter the latch. When any one
of the control signals returns to logic “1”, the data is latched.
A truth table for the control signals is presented in Table II.
27
1
0
1
1
1
1
LOGIC INPUT COMPATIBILITY
Input latches hold data temporarily while a complete 12-bit
word is assembled before loading into the D/A latch. This
double-buffered organization prevents the generation of spurious analog output values. Each latch is independently
addressable.
28
X
X
1
1
0
0
CAUTION: DAC813 was designed to use WR as the fast
strobe. WR has a much faster logic path than ENX (or
LDAC). Therefore, if one permanently wires WR to DCOM
and uses only ENX to strobe data into the latches, the
DATA HOLD time will be long, approximately 15ns to
30ns, and this time will vary considerably in this range
from unit to unit. DATA HOLD time using WR is 5ns max.
INTERFACE LOGIC
D7
X
X
0
1
1
0
TABLE II. DAC813 Interface Logic Truth Table.
DAC813 is a complete single IC chip 12-bit D/A converter.
The chip contains a 12-bit D/A converter, voltage reference,
output amplifier, and microcomputer-compatible input logic
as shown in Figure 1.
D8
X
X
1
0
1
0
“X” = Don’t Care
OPERATION
MSB
D11
LLSB LMSB LDAC RESET
1
X
0
0
0
0
Open DATA input lines will float to 7V or more. Although
this will not harm the DAC813, current spikes will occur in
the input lines when a logic 0 is asserted and, in addition,
22
21
20
19
18
LSB
D0
VL(1)
DCOM
17
1
16
24.9kΩ
4-Bit Latch
4
BPO
2
20V
Range
3
20V
Range
9
VOUT
25kΩ
LLSB
15
LDAC
12
Reset
13
8-Bit Latch
25kΩ
12-Bit D/A Latch
0–800µA
12-Bit D/A Converter
49.5kΩ
+10V
Reference
NOTE: (1) VL must be connected to +VCC.
7
6
5
8
10
VREF IN
VREF OUT
ACOM
+VCC
–VCC
FIGURE 1. DAC813 Block Diagram.
®
7
DAC813
1kΩ*
Digital
Input
BTC) configurations, apply the digital input code that should
produce the maximum negative output voltage and adjust
the offset potentiometer for minus full scale voltage. Example: If the full scale range is connected for 20V, the
maximum negative output voltage is –10V. See Table III for
corresponding codes.
See page 5
for II
6.8V
5pF
II
DCOM
* R = 500Ω for LLSB.
GAIN ADJUSTMENT
For either unipolar or bipolar configurations, apply the
digital input that should give the maximum positive voltage
output. Adjust the gain potentiometer for this positive full
scale voltage. See Table III for positive full scale voltages.
FIGURE 2. Equivalent Input Circuit for Digital Inputs.
the speed of the interface will be slower. A digital output
driving a DATA input line of the DAC813 must not drive,
or let the DATA input float, above +5.5V. Unused DATA
inputs should be connected to DCOM.
DIGITAL INPUT
RESET FUNCTION
When asserted low (<0.8V), RESET (Pin 13) forces the
D/A latch to 800HEX regardless of any other input logic
condition. If the analog output is connected for bipolar
operation (either ±10V or ±5V), the output will be reset to
Bipolar Zero (0V). If the analog output is connected for
unipolar operation (0 to +10V), the output will be reset to
half-scale (+5V).
MSB to LSB
0 to +10V
±5V
±10V
FFFHEX
800HEX
7FFHEX
000HEX
1LSB
+9.9976V
+5.0000V
+4.9976V
0.0000V
2.44mV
+4.9976V
0.0000V
–0.0024V
–5.0000V
2.44mV
+9.9951V
0.0000V
–0.0049V
–10.0000V
4.88mV
TABLE III. Digital Input/Analog Output.
INSTALLATION
If RESET is not used, it should be connected to a voltage
greater than +2V but not greater than +5.5V. If this voltage
is not available Reset can be connected to +VCC through a
100kΩ to 1MΩ resistor to limit the input current.
POWER SUPPLY CONNECTIONS
Note that the lid of the ceramic packaged DAC813 is
connected to –VCC. Take care to avoid accidental short
circuits in tightly spaced installations.
GAIN AND OFFSET ADJUSTMENTS
Figures 3 and 4 illustrate the relationship of offset and gain
adjustments to unipolar and bipolar D/A converter output.
Power supply decoupling capacitors should be added as
shown in Figure 5. Optimum settling performance occurs
using a 1 to 10µF tantalum capacitor at –VCC and at least a
0.01µF ceramic capacitor at +VCC. Applications with less
critical settling time may be able to use 0.01µF at –VCC as
well. The 0.01µF capacitors should be located close to the
DAC813.
Pin 1 supplies internal logic and must be connected to +VCC.
OFFSET ADJUSTMENT
For unipolar (USB) configurations, apply the digital input
code that should produce zero voltage output and adjust the
offset potentiometer for zero output. For bipolar (BOB,
Range of
Gain Adjust
≈ ±1%
+ Full Scale
ANALOG OUTPUT
Range of
Gain Adjust
≈ ±1%
+ Full Scale
1LSB
Full Scale Range
Range of
Offset Adj.
≈ ±0.4%
Gain Adjust
Rotates the Line
All Bits
Logic 0
Analog Output
Analog Output
1LSB
All Bits
Logic 1
Range of
Offset Adjust
Offset Adj.
Translates
the Line
≈ ±0.4%
Digital Input
Offset Adjust Translates the Line
FIGURE 3. Relationship of Offset and Gain Adjustments
for a Unipolar D/A Converter.
Full Scale
Range
Bipolar
Offset
Gain Adjust
Rotates the Line
MSB on All
Others Off
All Bits
Logic 1
– Full Scale
Digital Input
FIGURE 4. Relationship of Offset and Gain Adjustments
for a Bipolar D/A Converter.
®
DAC813
All Bits
Logic 0
8
200Ω
1kΩ
VOUT
+VCC
0.01µF
–VCC
(3)
1
VL
D11
28
2
20V Range D10
27
+VCC
3
20V Range
26
10k Ω to
100kΩ
D9
4
BPO
D8
25
5
ACOM
D7
24
6
V REF OUT
D6
23
7
V REF IN
D5
22
8
+VCC
D4
21
9
V OUT
D3
20
10
(2)
1kΩ
VOUT
+VCC
19
0.01µF
–VCC
VL
D11
28
2
20V Range D10
27
3
20V Range
D9
26
4
BPO
D8
25
5
ACOM
D7
24
6
V REF OUT
D6
23
7
V REF IN
D5
22
8
+VCC
D4
21
9
V OUT
D3
20
10
–VCC
D2
19
3MΩ
0.01µF
–VCC
1
(3)
–VCC
D2
11
WR
D1
18
11
WR
D1
18
12
LDAC
D0
17
12
LDAC
D0
17
13
Reset
DCOM
16
13
Reset
DCOM
16
14
LMSB
LLSB
15
14
LMSB
LLSB
15
+
+
0.01µF (1)
(1) 10µF tantalum for
optimum settling
performance.
(2) Unipolar offset is
not necessary in most
applications and can
lead to noise pickup.
(3) Note that for the
ceramic package
the lid is connected
to –VCC .
0.01µF (1)
BIPOLAR
UNIPOLAR
FIGURE 5. Power Supply, Gain, and Offset Connections.
APPLICATIONS
DAC813 features separate digital and analog power supply
returns to permit optimum connections for low noise and
high speed performance. It is recommended that both Analog Common (ACOM, Pin 5) and Digital Common (DCOM,
Pin 16) be connected directly to a ground plane under the
package. If a ground plane is not used, connect the ACOM
and DCOM pins together close to the package. Since the
reference point for VOUT and VREF OUT is the ACOM pin, it
is also important to connect the load directly to the ACOM
pin. Refer to Figure 5.
The change in current in the Analog Common pin (ACOM,
Pin 5) due to an input data word change from 000HEX to
FFFHEX is only 800µA.
MICROCOMPUTER BUS INTERFACING
The DAC813 interface logic allows easy interface to microcomputer bus structures. The control signal is derived from
external device select logic and the I/O Write or Memory
Write (depending upon the system design) signals from the
microcomputer.
The latch enable lines LMSB, LLSB, and LDAC determine
which of the latches are selected. It is permissible to enable
two or more latches simultaneously, as shown in some of the
following examples.
The double-buffered latch permits data to be loaded into the
input latches of several DAC813s and later strobed into the
D/A latch of all D/As, simultaneously updating all analog
outputs. All the interface schemes shown below use a base
address decoder. If blocks of memory are used, the base
address decoder can be simplified or eliminated altogether.
OUTPUT RANGE CONNECTIONS
Internal scaling resistors provided in the DAC813 may be
connected to produce bipolar output voltage ranges of ±10V
and ±5V or unipolar output voltage range of 0 to +10V.
Refer to Figure 6.
The internal feedback resistors (25kΩ) and the bipolar offset
resistor (24.9kΩ) are trimmed to an absolute tolerance of
less than ±2%. Therefore, one can change the range by
adding a series resistor in various feedback circuit configurations. For example, a 600Ω resistor in series with the 20V
range terminal can be used to obtain a 20.48V (±10.24V)
range (5mV LSB). A 7.98kΩ resistor in series with the 10V
range connection (20V ranges in parallel) gives a 16.384V
(±8.192V) bipolar range (4mV LSB). Gain drift will be
affected by the mismatch of the temperature coefficient of
the external resistor with the internal D/A resistors.
8-BIT INTERFACE
The control logic of DAC813 permits interfacing to rightjustified data formats, illustrated in Figure 7. When a 12-bit
D/A converter is loaded from an 8-bit bus, two bytes of data
are required. Figure 8 illustrates an addressing scheme for
right-justified data. The base address is decoded from the
high-order address bits. A0 and A1 address the appropriate
latches. Note that adjacent addresses are used. X10HEX loads
the 8 LSBs and X01HEX loads the 4 MSBs and simultaneously transfers input latch data to the D/A latch. Addresses
X00HEX and X11HEX are not used.
®
9
DAC813
INTERFACING MULTIPLE
DAC813s IN 8-BIT SYSTEMS
Many applications, such as automatic test systems, require
that the outputs of several D/A converters be updated simultaneously. The interface shown in Figure 9 uses a 74LSB138
decoder to decode a set of eight adjacent addresses to load
the input latches of four DAC813s. The example uses a
right-justified data format.
A ninth address using A3 causes all DAC813s to be updated
simultaneously. If a certain DAC813 is always loaded last
(for instance, D/A #4), A3 is not needed, saving 8 address
24.9kΩ
spaces for other uses. Incorporate A3 into the base address
decoder, remove the inverter, connect the common LDAC
line to LLSB of D/A #4, and connect D1 of the 74LS138 to
+5V.
12- AND 16-BIT MICROCOMPUTER INTERFACE
For this application the input latch enable lines, LMSB and
LLSB, are tied low, causing the latches to be transparent.
The D/A latch, and therefore DAC813, is selected by the
address decoder and strobed by WR.
Be sure and read the CAUTION statement in the LOGIC
INPUT COMPATIBILITY section.
NC
X
4
BPO
20V
25kΩ
3
X
X D11 D10 D9 D8
D7 D6 D5 D4 D3 D2 D1 D0
Right-Justified
25kΩ
2
X
FIGURE 7. 12-Bit Data Format for 8-Bit Systems.
0 TO +10V
RANGE
20V
17
D0
25
D8
18
D1
26
D9
19
D2
27
D10
20
D3
28
D11
DB4
21
D4
DB5
22
D5
DB6
23
D6
DB7
24
D7
11
WR
12
LDAC
14
LMSB
15
LLSB
13
Reset
DB0
9
I DAC
VOUT
0 to +10V
DB1
6
ACOM
DB2
VREF OUT
24.9kΩ
BPO
25kΩ
2
20V
25kΩ
3
NC
DB3
200Ω pot or
100Ω fixed
Microcomputer
4
±10V
RANGE
20V
9
I DAC
5
6
VOUT
WR
±10V
A15
ACOM
A2
VREF OUT
Base
Address
Decoder
A1
24.9kΩ
4
BPO
25kΩ
2
20V
25kΩ
3
9
I DAC
5
A0
200Ω pot or
100Ω fixed
Reset Circuitry
±5V
RANGE
FIGURE 8. Right-Justified Data Bus Interface.
20V
VOUT
±5V
ACOM
FIGURE 6. Output Amplifier Voltage Range Scaling Circuit.
®
DAC813
DAC813
5
10
WR
A15
WR
Base
Address
Decoder
A4
LDAC DAC813
(1)
LLSB
CS
LMSB
A3
WR
15
LDAC DAC813
(2)
LLSB
14
LMSB
Microcomputer
74LS138
4
5
6
G2A
G2B
G1
Y0
Y1
Y2
Y3
13
12
Y4 11
3
A2
2
A1
1
A0
A3
Y5 10
C
B
Y6
A
Y7
ADDRESS BUS
A2
A1
A0
9
7
WR
LDAC DAC813
(4)
LLSB
LMSB
OPERATION
0
0
0
0
Load 8 LSB – D/A #1
0
0
0
1
Load 4 MSB – D/A #1
0
0
1
0
Load 8 LSB – D/A #2
0
0
1
1
Load 4 MSB – D/A #2
0
1
0
0
Load 8 LSB – D/A #3
0
1
0
1
Load 4 MSB – D/A #3
0
1
1
0
Load 8 LSB – D/A #4
0
1
1
1
Load 4 MSB – D/A #4
1
X
X
X
Load D/A Latch—All D/A
FIGURE 9. Interfacing Multiple DAC813s to an 8-Bit Bus.
®
11
DAC813
PACKAGE OPTION ADDENDUM
www.ti.com
24-Aug-2018
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
DAC813AU
ACTIVE
SOIC
DW
28
20
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC813AU
DAC813AU/1K
ACTIVE
SOIC
DW
28
1000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC813AU
DAC813AUG4
ACTIVE
SOIC
DW
28
20
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC813AU
DAC813JU
ACTIVE
SOIC
DW
28
20
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
0 to 70
DAC813JU
DAC813JU/1K
ACTIVE
SOIC
DW
28
1000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
0 to 70
DAC813JU
DAC813KU
ACTIVE
SOIC
DW
28
20
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
0 to 70
DAC813KU
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
24-Aug-2018
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Feb-2019
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
DAC813AU/1K
SOIC
DW
28
1000
330.0
32.4
11.35
18.67
3.1
16.0
32.0
Q1
DAC813JU/1K
SOIC
DW
28
1000
330.0
32.4
11.35
18.67
3.1
16.0
32.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Feb-2019
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
DAC813AU/1K
SOIC
DW
28
1000
350.0
350.0
66.0
DAC813JU/1K
SOIC
DW
28
1000
350.0
350.0
66.0
Pack Materials-Page 2
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