MAX3514/MAX3516/MAX3517 Upstream CATV Amplifiers

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ION KIT
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A
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AVAILA
Upstream CATV Amplifiers
The MAX3514 is a pin-for-pin compatible upgrade for
the MAX3510. Like the MAX3510, the MAX3514 is internally matched for use with a 2:1 (voltage ratio) balun.
The MAX3517 utilizes an external output resistor for
greater load-matching flexibility, and offers the same
performance as the MAX3514. The MAX3516 is a higher power version of the MAX3514 with 3dB more gain
and output power capability, and is offered in a smaller
thermally enhanced TSSOP-EP package.
These devices operate from a single +5V DC supply
and draw 120mA during transmit (100% duty cycle,
+61dBmV out). The bias current is automatically adjusted based on the output level to increase efficiency.
Additionally, the devices are shut off between bursts to
minimize noise and save power while still maintaining a
match at the output port. Shutdown mode disables all
circuitry and reduces current consumption to 10µA
(typ).
The MAX3514/MAX3517 are available in a 20-pin QSOP
package and the MAX3516 is available in a 20-pin
TSSOP-EP package. All devices operate in the extended industrial temperature range (-40°C to +85°C).
________________________Applications
DOCSIS/EuroDOCSIS and DVB Cable
Modems
OpenCable Set-Top Box
Features
♦ Accurate Gain Control
♦ Gain Programmable in 0.5dB Steps
♦ 56dB of Gain Control Range
♦ -55dBc Harmonic Distortion at 65MHz Input
♦ Low Burst On/Off Transient
♦ High Efficiency:
35mA at +34dBmV Out
9mA Transmit Disable Mode
Ordering Information
-40°C to +85°C
PINPACKAGE
20 QSOP
MAX3516EUP
-40°C to +85°C
20 TSSOP-EP*
MAX3517EEP
-40°C to +85°C
20 QSOP
PART
TEMP RANGE
MAX3514EEP
*Exposed paddle
Pin Configuration
TOP VIEW
GND 1
20 GND
VCC 2
19 VCC
GND 3
18 TXEN
GND 4
17 N.C.
Telephony over Cable
IN+ 5
CATV Status Monitor
IN- 6
MAX3514
MAX3516
MAX3517
GND 7
Typical Operating Circuit appears at end of data sheet.
SDA 9
15 OUT14 CEXT (N.C.)
CS 8
SCLK 10
16 OUT+
13 N.C.
EXPOSED
PADDLE*
12 SHDN
11 GND
SPI is a trademark of Motorola Corp.
DOCSIS/EuroDOCSIS/OpenCable are trademarks of
CableLabs.
( ) FOR MAX3517 ONLY
* MAX3516 ONLY
QSOP/TSSOP-EP
________________________________________________________________ Maxim Integrated Products
1
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
MAX3514/MAX3516/MAX3517
General Description
The MAX3514/MAX3516/MAX3517 programmable-gain
amplifiers are designed for use in CATV upstream
applications. The MAX3514/MAX3517 drive up to
+61dBmV (QPSK) into a 75Ω load when driven with a
+34dBmV nominal input signal. The MAX3516 drives
up to +64dBmV (QPSK). Both input and output ports
are differential, requiring that an external balun be used
at the output port. The variable gain feature provides
greater than 56dB of dynamic range, which is controlled by an SPI™ 3-wire interface. Gain control is
available in 0.5dB steps. The devices operate over a
frequency range of 5MHz to 65MHz.
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
ABSOLUTE MAXIMUM RATINGS
VCC, OUT+, OUT-................................................-0.3V to +10.0V
Input Voltage Levels (all inputs) .................-0.3V to (VCC + 0.3V)
Continuous Input Voltage (IN+, IN-) ...................................2Vp-p
Continuous Current (OUT+, OUT-) ...................................120mA
Continuous Power Dissipation (TA = +70°C)
20-Pin QSOP (derate 12.3mW/°C above TA = +70°C). .988mW
20-Pin TSSOP-EP
(derate 27mW/°C above TA = +70°C) .......................2200mW
Operating Temperature Range .......................... -40°C to +85°C
Junction Temperature ..................................................... +150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10s) ................................ +300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS—MAX3514/MAX3516/MAX3517
(Typical operating circuit; VCC = +4.75V to +5.25V, VGND = 0, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at
VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
Supply Voltage
SYMBOL
CONDITIONS
VCC
MIN
TYP
4.75
D7 = 1, gain code = 125 (AV = 27dB)
120
D7 = 0, gain code = 100 (AV = 0dB)
35
D7 = 1, gain code = 125 (AV = 30dB)
160
D7 = 0, gain code = 94 (AV = 0dB)
30
ICC
TXEN = low
9
ICC
SHDN = low
10
Supply Current Transmit Mode
(MAX3514/MAX3517)
ICC
Supply Current Transmit Mode
(MAX3516)
ICC
Supply Current Transmit Disable
Mode
Supply Current Low-Power
Standby
MAX
UNITS
5.25
V
150
190
12
mA
mA
mA
µA
LOGIC INPUTS
Input High Voltage
VINH
Input Low Voltage
VINL
Input High Current
IBIASH
VINH = +3.6V
Input Low Current
IBIASL
VINL = 0
2
2.0
-100
_______________________________________________________________________________________
V
0.8
V
100
µA
µA
Upstream CATV Amplifiers
(MAX3514 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
Voltage Gain, fIN = 5MHz
(Note 2)
Voltage Gain, fIN = 65MHz
SYMBOL
AV
AV
CONDITIONS
D7 = 1, gain code = 125, TA = 0°C to +85°C
MIN
26.7
TYP
27.7
MAX
28.7
D7 = 1, gain code = 110, TA = 0°C to +85°C
19.2
20.2
21.2
D7 = 1, gain code = 90, TA = 0°C to +85°C
9.2
10.2
11.2
D7 = 1, gain code = 70, TA = 0°C to +85°C
-0.8
0.2
1.2
D7 = 0, gain code = 115, TA = 0°C to +85°C
6.7
7.7
8.7
D7 = 0, gain code = 100, TA = 0°C to +85°C
-0.8
0.2
1.2
D7 = 0, gain code = 80, TA = 0°C to +85°C
-10.8
-9.8
-8.8
D7 = 0, gain code = 60, TA = 0°C to +85°C
-20.8
-19.8
-18.8
D7 = 0, gain code = 48, TA = 0°C to +85°C
-27.0
-26.0
-25.0
D7 = 1, gain code = 127, TA = -40°C to
+85°C; Notes 3, 4
25.7
fIN = 5MHz to 65MHz, AV = -26dB to +27dB
Gain Step Size
1
1.3
fIN = 5MHz to 42MHz, D7 = 0,
gain code = 115; to D7 = 1, gain code = 87
0.6
1.0
1.4
Isolation in Transmit-Disable
Mode
TXEN = low, fIN = 5MHz to 65MHz
Transmit Mode Noise
BW = 160kHz, fIN = 5MHz to 65MHz,
AV = -26dB to +27dB; Note 3
Transmit Enable Transient
Duration
Transmit Disable Transient
Duration
Transmit Disable/Transmit Enable
Transient Step Size
Input Impedance
Output Return Loss
ZIN
0.5
0.7
TXEN = low, BW = 160kHz, fIN = 5MHz to
65MHz; Note 3
dB
dB
fIN = 5MHz to 65MHz, AV = -26dB to +27dB,
any 2-bit transition of D0, D1
Transmit-Disable Mode Noise
UNITS
-71
50
58
dB
dBmV
dB
-59
dBc
TXEN input rise/fall time < 0.1µs, TA = +25°C;
Note 3
2
µs
TXEN input rise/fall time < 0.1µs, TA = +25°C;
Note 3
2
µs
D7 = 1, gain code = 125 (AV = 27dB),
TA = +25°C
30
D7 = 0, gain code = 100 (AV = 0.2dB),
TA = +25°C
1
100
mVp-p
fIN = 5MHz to 65MHz, single ended; Note 3
1
1.5
kΩ
fIN = 5MHz to 42MHz in 75Ω system, D7 = 1
gain code = 125 (AV = 27dB); Notes 3, 4
6.2
8.3
dB
_______________________________________________________________________________________
3
MAX3514/MAX3516/MAX3517
AC ELECTRICAL CHARACTERISTICS—MAX3514
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
AC ELECTRICAL CHARACTERISTICS—MAX3514 (continued)
(MAX3514 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
SYMBOL
Output Return Loss in TransmitDisable Mode
Two-Tone Third-Order Distortion
CONDITIONS
fIN = 5MHz to 42MHz, in 75Ω system,
TXEN = low; Note 4
IM3
2nd-Harmonic Distortion
HD2
3rd-Harmonic Distortion
HD3
MIN
TYP
6.1
10.5
MAX
UNITS
dB
Input tones at 42MHz and 42.2MHz, both
+31dBmV, VOUT = +58dBmV/tone; Note 3
-51
Input tones at 65MHz and 65.2MHz, both
+31dBmV, VOUT = +58dBmV/tone
-46
fIN = 33MHz, VOUT = +61dBmV; Note 3
-55
-53
fIN = 65MHz, VOUT = +61dBmV; Note 3
-55
-52
fIN = 22MHz, VOUT = +61dBmV
-55
-49
fIN = 65MHz, VOUT = +61dBmV
-55
-49
-46
dBc
dBc
dBc
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to +38dBmV,
fIN = 42MHz
0.1
dB
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to +38dBmV,
fIN = 65MHz
0.1
dB
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to +38dBmV,
fIN = 42MHz
1
degrees
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to +38dBmV,
fIN = 65MHz
1
degrees
4
_______________________________________________________________________________________
Upstream CATV Amplifiers
(MAX3516 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
Voltage Gain, fIN = 5MHz
SYMBOL
AV
CONDITIONS
MIN
TYP
MAX
D7 = 1, gain code = 127,
TA = 0°C to +85°C
31
32
33
D7 = 1, gain code = 119,
TA = 0°C to +85°C
27
28
29
D7 = 1, gain code = 104,
TA = 0°C to +85°C
19.5
20.5
21.5
D7 = 1, gain code = 84,
TA = 0°C to +85°C
9.5
10.5
11.5
D7 = 1, gain code = 64,
TA = 0°C to +85°C
-0.5
0.5
1.5
D7 = 1, gain code = 109,
TA = 0°C to +85°C
7
8
9
D7 = 1, gain code = 94,
TA = 0°C to +85°C
-0.5
0.5
1.5
D7 = 0, gain code = 74,
TA = 0°C to +85°C
-10.5
-9.5
-8.5
D7 = 0, gain code = 54,
TA = 0°C to +85°C
-20.5
-19.5
-18.5
D7 = 0, gain code = 42,
TA = 0°C to +85°C
-26.5
-25.5
-24.5
UNITS
dB
Gain Step Size
fIN = 5MHz to 65MHz,
AV = -26dB to +27dB
0.5
dB
Transmit-Disable Mode Noise
TXEN = low, BW = 160kHz,
fIN = 5MHz to 65MHz
-71
dBmV
Isolation in Transmit-Disable
Mode
TXEN = low, fIN = 5MHz to 65MHz
58
dB
Transmit Mode Noise
BW = 160kHz, fIN = 5MHz to 65MHz,
AV = -26dB to +27dB; Note 3
Transmit Enable Transient
Duration
TXEN input rise/fall time < 0.1µs,
TA = +25°C; Note 3
50
-59
dBc
2
µs
_______________________________________________________________________________________
5
MAX3514/MAX3516/MAX3517
AC ELECTRICAL CHARACTERISTICS—MAX3516 (Preliminary)
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
AC ELECTRICAL CHARACTERISTICS—MAX3516 (Preliminary) (continued)
(MAX3516 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
SYMBOL
Transmit Disable
Transient Duration
MIN
TYP
TXEN input rise/fall time < 0.1µs,
TA = +25°C
Transmit Disable/Transmit Enable
Transient Step Size
Input Impedance
CONDITIONS
ZIN
D7 = 1, gain code = 125,
(AV = 27dB), TA = +25°C
30
D7 = 0, gain code = 100,
(AV = 0.2 dB), TA = +25°C
1
fIN = 5MHz to 65MHz, single ended;
Note 3
MAX
UNITS
2
µs
100
mVp-p
1
1.5
kΩ
Output Return Loss
fIN = 5MHz to 65MHz in 75Ω system
D7 = 1, gain code = 125,
(AV = 30dB); Note 4
8.2
dB
Output Return Loss in TransmitDisable Mode
fIN = 42MHz, in 75Ω system
TXEN = low; Note 4
10.5
dB
Input tones at 42MHz and 42.2MHz,
both +31dBmV, VOUT = +58dBmV/tone
-53.5
Input tones at 65MHz and 65.2MHz,
both +31dBmV, VOUT = +58dBmV/tone
-48.8
Two-Tone Third-Order Distortion
(Note 2)
2nd-Harmonic Distortion
3rd-Harmonic Distortion
1dB Compression Point
IM3
HD2
HD3
P1dB
dBc
fIN = 33MHz, VOUT = +61dBmV
-55
fIN = 33MHz, VOUT = +64dBmV
-55
fIN = 65MHz, VOUT = +61dBmV
-55
fIN = 22MHz, VOUT = +61dBmV
-55
fIN = 22MHz, VOUT = +64dBmV
-50
fIN = 65MHz, VOUT = +61dBmV
-55
AV = 27dB at 65MHz
20
dBc
dBc
22
dBm
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 42MHz
0.1
dB
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 65MHz
0.1
dB
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 42MHz
1
degrees
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 65MHz
1
degrees
6
_______________________________________________________________________________________
Upstream CATV Amplifiers
(MAX3517 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
Voltage Gain, fIN = 5MHz
SYMBOL
AV
CONDITIONS
MIN
TYP
MAX
D7 = 1, gain code = 125,
TA = 0°C to +85°C
26.7
27.7
28.7
D7 = 1, gain code = 110,
TA = 0°C to +85°C
19.2
20.2
21.2
D7 = 1, gain code = 90,
TA = 0°C to +85°C
9.2
10.2
11.2
D7 = 1, gain code = 70,
TA = 0°C to +85°C
-0.8
0.2
1.2
D7 = 1, gain code = 115,
TA = 0°C to +85°C
6.7
7.7
8.7
D7 = 1, gain code = 100,
TA = 0°C to +85°C
-0.8
0.2
1.2
D7 = 1, gain code = 80,
TA = 0°C to +85°C
-10.8
-9.8
-8.8
D7 = 0, gain code = 60,
TA = 0°C to +85°C
-20.8
-19.8
-18.8
D7 = 0, gain code = 48,
TA = 0°C to +85°C
-27.0
-26.0
-25.0
UNITS
dB
Gain Step Size
fIN = 5MHz to 65MHz,
AV = -26dB to +27dB
0.5
dB
Transmit-Disable Mode Noise
TXEN = low, BW = 160kHz,
fIN = 5MHz to 65MHz
-71
dBmV
Isolation in Transmit-Disable
Mode
TXEN = low, fIN = 5MHz to 65MHz
58
dB
Transmit Mode Noise
BW = 160kHz, fIN = 5MHz to 65MHz,
AV = -26dB to +27dB; Note 3
Transmit Enable Transient
Duration
TXEN input rise/fall time < 0.1µs,
TA = +25°C; Note 3
50
-60
-59
dBc
2
µs
_______________________________________________________________________________________
7
MAX3514/MAX3516/MAX3517
AC ELECTRICAL CHARACTERISTICS—MAX3517 (Preliminary)
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
AC ELECTRICAL CHARACTERISTICS—MAX3517 (Preliminary) (continued)
(MAX3517 EV kit; VCC = +4.75V to +5.25V, VGND = 0, PIN = +34dBmV, TXEN = SHDN = high, TA = -40°C to +85°C. Typical parameters are at VCC = +5V, TA = +25°C, unless otherwise specified.) (Note 1)
PARAMETER
SYMBOL
Transmit Disable
Transient Duration
MIN
TYP
TXEN input rise/fall time < 0.1µs,
TA = +25°C
Transmit Disable/Transmit Enable
Transient Step Size
Input Impedance
CONDITIONS
ZIN
D7 = 1, gain code = 125,
(AV = 27dB), TA = +25°C
30
D7 = 0, gain code = 100,
(AV = 0.2 dB), TA = +25°C
1
fIN = 5MHz to 65MHz, single ended;
Note 3
MAX
UNITS
2
µs
100
mVp-p
1
1.5
kΩ
Output Return Loss
fIN = 5MHz to 65MHz in 75Ω system
D7 = 1, gain code = 125,
(AV = 27dB); Note 4
8.3
dB
Output Return Loss in TransmitDisable Mode
fIN = 42MHz, in 75Ω system
TXEN = low; Note 4
10.5
dB
Input tones at 42MHz and 42.2MHz,
both +31dBmV, VOUT = +58dBmV/tone
-49.5
Input tones at 65MHz and 65.2MHz,
both +31dBmV, VOUT = +58dBmV/tone
-46.3
Two-Tone Third-Order Distortion
(Note 2)
IM3
2nd-Harmonic Distortion
HD2
3rd-Harmonic Distortion
HD3
dBc
fIN = 33MHz, VOUT = +61dBmV
-55
fIN = 65MHz, VOUT = +61dBmV
-55
fIN = 22MHz, VOUT = +61dBmV
-55
fIN = 65MHz, VOUT = +61dBmV
-55
dBc
dBc
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 42MHz
0.1
dB
AM to AM
AM/AM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 65MHz
0.1
dB
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 42MHz
1
degrees
AM to PM
AM/PM
AV = 27dB, VIN = +34dBmV to
+38dBmV, fIN = 65MHz
1
degrees
8
_______________________________________________________________________________________
Upstream CATV Amplifiers
(VCC = 4.75V to 5.25V, VGND = 0, TXEN = SHDN = high, D7 = X, TA = +25°C, unless otherwise specified.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SEN to SCLK Rise Set Time
tSENS
20
ns
SEN to SCLK Rise Hold Time
tSENH
10
ns
SDA to SCLK Setup Time
tSDAS
20
ns
SDA to SCLK Hold Time
tSDAH
10
ns
SDA Pulse Width High
TDATAH
50
ns
SDA Pulse Width Low
TDATAL
50
ns
SCLK Pulse Width High
tSCLKH
50
ns
SCLK Pulse Width Low
tSCLKL
50
ns
Note 1:
Note 2:
Note 3:
Note 4:
Guaranteed by design and characterization to ±3 sigma for TA < +25°C, unless otherwise specified.
AC Gain correlated to DC Gain measurements to ±3 sigma.
Guaranteed by design and characterization to ±6 sigma.
Does not include output matching; see Output Match in the Applications section.
_______________________________________________________________________________________
9
MAX3514/MAX3516/MAX3517
TIMING CHARACTERISTICS
__________________________________________Typical Operating Characteristics
(Typical operating circuit; VCC = +5V, VIN = +34dBmV, TXEN = SHDN = high, fIN = 20MHz, ZLOAD = 75Ω, TA = +25°C, unless
otherwise noted.)
MAX3514/MAX3517
VOLTAGE GAIN vs. SUPPLY VOLTAGE
HIGH-POWER MODE
80
TRANSMIT-ENABLE MODE
LOW-NOISE, GAIN CODE = 100
40
TRANSMIT-DISABLE MODE
20
27.8
27.6
-25
0
25
50
75
TA = -40°C
-26.0
-26.4
-26.6
27.2
-26.8
-27.0
4.7
4.8
4.9
5.0
5.1
5.2
5.3
4.7
5.0
5.1
5.2
VOLTAGE GAIN vs. FREQUENCY
HIGH-POWER MODE
28.4
-9.6
VCC = +5.00V
-9.8
-10.0
40
VOLTAGE GAIN (dB)
VCC = +5.25V
GAIN CODE = 80
-9.4
VOLTAGE GAIN (dB)
28.8
VCC = +4.75V
-9.2
VCC = +4.75V
-10.2
VCC = +5.25V
-10.4
35
60
85
-15
10
35
60
TEMPERATURE (°C)
TEMPERATURE (°C)
VOLTAGE GAIN vs. FREQUENCY
LOW-NOISE MODE
VOLTAGE GAIN vs. GAIN CODE
AT 20MHz
A
B
0
C
-10
D
-20
E
-30
F
VOLTAGE GAIN (dB)
10
-40
GAIN CODE:
A = 120, B = 115, C = 95,
D = 75, E = 55, F = 35
-70
10
100
FREQUENCY (MHz)
1000
10
C
0
D
-10
GAIN CODE:
A = 125, B = 100,
C = 80, D = 60
35
30
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
-35
1
85
HIGH-POWER MODE
LOW- NOISE MODE
100
10
1000
FREQUENCY (MHz)
GAIN STEP vs. GAIN CODE
HIGH-POWER MODE AT 20MHz
MAX3514 toc08
MAX3514 toc07
30
20
B
-40
-11.0
-40
1.0
0.9
0.8
GAIN STEP (dB)
10
20
-30
-10.8
-15
A
-20
-10.6
28.2
30
5.3
MAX3514 toc06
-9.0
MAX3514 toc04
VCC = +5.00V
29.0
1
4.9
VOLTAGE GAIN vs. TEMPERATURE
LOW-NOISE MODE
29.2
-60
4.8
VOLTAGE GAIN vs. TEMPERATURE
HIGH-POWER MODE
29.4
-50
TA = +85°C
SUPPLY VOLTAGE (V)
29.6
28.0
-40
TA = +25°C
-26.2
27.4
100
TA = -40°C
-25.8
SUPPLY VOLTAGE (V)
GAIN CODE = 127
28.6
-25.6
TEMPERATURE (°C)
30.0
29.8
-25.4
MAX3514 toc05
-50
VOLTAGE GAIN (dB)
TA = +25°C
27.0
0
10
TA = +85°C
28.0
GAIN CODE = 48
-25.2
MAX3514 toc09
60
28.4
28.2
-25.0
VOLTAGE GAIN (dB)
TRANSMIT-ENABLE MODE
HIGH-POWER, GAIN CODE = 125
100
GAIN CODE = 125
28.6
VOLTAGE GAIN (dB)
120
28.8
MAX3514 toc02
140
SUPPLY CURRENT (mA)
29.0
MAX3514 toc01
160
VOLTAGE GAIN vs. SUPPLY VOLTAGE
LOW-NOISE MODE
MAX3514 toc03
SUPPLY CURRENT vs. TEMPERATURE
VOLTAGE GAIN (dB)
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
0.7
0.6
0.5
0.4
0.3
0.2
0.1
30 40
50 60 70
80 90 100 110 120
GAIN CODE
0
60
70
80
90
100
GAIN CODE
______________________________________________________________________________________
110
120
Upstream CATV Amplifiers
(Typical operating circuit; VCC = +5V, VIN = +34dBmV, TXEN = SHDN = high, fIN = 20MHz, ZLOAD = 75Ω, TA = +25°C, unless
otherwise noted.)
MAX3514/MAX3517 (continued)
GAIN STEP vs. GAIN CODE
LOW-NOISE MODE AT 20MHz
0.7
0.6
0.5
0.4
0.3
0.2
MAX3514 toc11
0.8
-20
OUTPUT NOISE (dBmV IN 160kHz)
0.9
-25
HIGH-POWER MODE
-30
-35
-40
-45
LOW-NOISE MODE
-50
0.1
0
-55
50
60 70
30
80 90 100 110 120
50
70
-10
110
130
OUTPUT SPECTRUM
OUTPUT SPECTRUM
10
0
90
GAIN CODE
GAIN CODE
VOUT = +61dBmV
α = 0.25
1280ksps
10
0
-10
-20
-20
-30
-30
-40
-40
-50
-50
-60
-60
-70
-70
-80
-80
MAX3514 toc17
30 40
MAX3514 toc16
GAIN STEP (dB)
TRANSMIT NOISE vs. GAIN CODE
MAX3514 toc10
1.0
VOUT = +61dBmV
α = 0.25
160ksps
-90
-90
CENTER 20 MHz
500kHz
SPAN 5MHz
CENTER 20MHz
100kHz
SPAN 1MHz
______________________________________________________________________________________
11
MAX3514/MAX3516/MAX3517
Typical Operating Characteristics (continued)
Typical Operating Characteristics (continued)
(Typical operating circuit; VCC = +5V, VIN = +34dBmV, TXEN = SHDN = high, fIN = 20MHz, ZLOAD = 75Ω, TA = +25°C, unless
otherwise noted.)
MAX3516
VOLTAGE GAIN vs. SUPPLY VOLTAGE
HIGH-POWER MODE
TRANSMIT-ENABLE MODE
HIGH-POWER, GAIN CODE = 119
100
80
60
TRANSMIT-ENABLE MODE,
LOW-NOISE, GAIN CODE = 94
40
20
TRANSMIT-DISABLE MODE
28.2
28.0
-25
0
25
50
75
TA = +25°C
TA = +85°C
27.8
27.6
-25.0
-25.2
-25.6
27.2
-25.8
-26.0
4.7
4.8
4.9
5.0
5.1
5.2
5.3
4.7
4.8
4.9
5.0
5.1
5.2
VOLTAGE GAIN vs. FREQUENCY
HIGH-POWER MODE
-9.1
28.6
28.4
VCC = +5.00V
-9.3
-9.5
-9.7
VCC = +4.75V
-9.9
A
30
10
35
60
85
C
10
D
0
E
-10
GAIN CODE:
A = 125, B = 119,
C = 94, D = 74, E = 54
-30
-10.3
-15
B
20
-20
VCC = +5.25V
-10.1
28.2
40
VOLTAGE GAIN (dB)
VCC = +5.25V
GAIN CODE = 74
-8.9
VOLTAGE GAIN (dB)
29.0
VCC = +4.75V
-8.7
-10.5
-40
-40
-15
10
35
60
1
85
100
10
1000
TEMPERATURE (°C)
TEMPERATURE (°C)
FREQUENCY (MHz)
VOLTAGE GAIN vs. FREQUENCY
LOW-NOISE MODE
VOLTAGE GAIN vs. GAIN CODE
AT 20MHz
GAIN STEP vs. GAIN CODE
HIGH-POWER MODE AT 20MHz
C
-10
D
-20
E
-30
F
VOLTAGE GAIN (dB)
B
0
-40
GAIN CODE:
A = 114, B = 109, C = 89,
D = 69, E = 49, F = 29
-70
10
100
FREQUENCY (MHz)
1000
HIGH-POWER MODE
LOW- NOISE MODE
MAX3514 toc27
1.0
0.9
0.8
GAIN STEP (dB)
A
10
35
30
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
-35
MAX3514 toc26
MAX3514 toc25
30
20
5.3
MAX3514 toc24
-8.5
MAX3514 toc22
29.2
1
TA = +85°C
VOLTAGE GAIN vs. TEMPERATURE
LOW-NOISE MODE
VCC = +5.00V
-60
TA = +25°C
-25.4
VOLTAGE GAIN vs. TEMPERATURE
HIGH-POWER MODE
29.4
-50
TA = -40°C
-24.8
SUPPLY VOLTAGE (V)
29.6
28.0
-40
MAX3514 toc21
-24.6
SUPPLY VOLTAGE (V)
GAIN CODE = 121
28.8
-24.4
27.4
100
GAIN CODE = 42
-24.2
TEMPERATURE (°C)
30.0
29.8
-24.0
MAX3514 toc23
-50
VOLTAGE GAIN (dB)
TA = -40°C
28.4
27.0
0
12
GAIN CODE = 119
28.6
VOLTAGE GAIN (dB)
120
28.8
MAX3514 toc20
140
SUPPLY CURRENT (mA)
29.0
MAX3514 toc19
160
VOLTAGE GAIN vs. SUPPLY VOLTAGE
LOW-NOISE MODE
VOLTAGE GAIN (dB)
SUPPLY CURRENT vs. TEMPERATURE
VOLTAGE GAIN (dB)
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
25 35 45 55 65 75 85 95 105 115 125
GAIN CODE
55
65
75
85
95
GAIN CODE
______________________________________________________________________________________
105
115
125
Upstream CATV Amplifiers
(Typical operating circuit; VCC = +5V, VIN = +34dBmV, TXEN = SHDN = high, fIN = 20MHz, ZLOAD = 75Ω, TA = +25°C, unless
otherwise noted.)
0.8
0.7
0.6
0.5
0.4
0.3
0.2
-20
MAX3514 toc29
0.9
GAIN STEP (dB)
TRANSMIT NOISE vs. GAIN CODE
MAX3514 toc28
1.0
MAX3516 (continued)
OUTPUT NOISE (dBmV IN 160kHz)
GAIN STEP vs. GAIN CODE
LOW-NOISE MODE AT 20MHz
-25
-30
HIGH-POWER MODE
-35
-40
-45
LOW-NOISE MODE
-50
0.1
0
-55
20 30 40 50 60 70 80 90 100 110 120
25
GAIN CODE
45
65
85
105
125
GAIN CODE
Pin Description
PIN
NAME
FUNCTION
1, 3, 7, 11
GND
Ground
2
VCC
Programmable-Gain Amplifier (PGA) +5V Supply. Bypass to pin 4 with a decoupling capacitor as
close to the part as possible.
4
GND
PGA RF Ground. As with all ground connections, maintain the shortest possible (low-inductance)
length to the ground plane.
5
IN+
Positive PGA Input. Along with IN-, this port forms a high-impedance differential input to the PGA.
Driving this port differentially increases the rejection of second-order distortion at low output levels.
6
IN-
Negative PGA Input. When not used, this port must be AC-coupled to ground. See IN+.
8
CS
Serial-Interface Enable. TTL-compatible input. See Serial Interface section.
9
SDA
Serial-Interface Data. TTL-compatible input. See Serial Interface section.
10
SCLK
Serial-Interface Clock. TTL-compatible input. See Serial Interface section.
12
SHDN
Shutdown. When SHDN is set low, all functions (including the serial interface) are disabled.
13, 17
N.C.
No Connection
14
CEXT
RF Output Bypass. Bypass to ground with a 0.1µF capacitor. (N.C. for MAX3517.)
15
OUT-
Negative Output. Along with OUT+, this port forms a 300Ω impedance output. This port is matched
to a 75Ω load using a 2:1 (voltage ratio) transformer.
16
OUT+
Positive Output. See OUT-.
18
TXEN
Transmit Enable. Drive TXEN high to place the device in transmit-enable mode.
19
VCC
Output Amplifier Bias, +5V Supply. Bypass to pin 20 with a decoupling capacitor as close to the part
as possible.
20
GND
Output Amplifier Bias Ground. As with all ground connections, maintain the shortest possible (lowinductance) length to the ground plane.
Exposed
Paddle
GND
Ground (MAX3516 only)
______________________________________________________________________________________
13
MAX3514/MAX3516/MAX3517
Typical Operating Characteristics (continued)
Upstream CATV Amplifiers
MAX3514/MAX3516/MAX3517
Functional Diagram
TXEN
SHDN
VCC
BIAS
CONTROL
MAX3514
MAX3516
MAX3517
HIGH
POWER
OUTCEXT
IN+
OUT+
IN-
*
LOW
NOISE
D/A CONVERTER
SERIAL DATA INTERFACE
CS SDA SCLK
Detailed Description
Programmable-Gain Amplifier
The PGA consists of the variable-gain amplifier (VGA)
and the digital-to-analog converter (DAC), which provide better than 56dB of output level control in 0.5dB
steps. The PGA is implemented as a programmable
Gilbert-cell attenuator. The gain of the PGA is determined by a 7-bit word (D6–D0) programmed through
the serial data interface (Tables 1 and 2).
Specified performance is achieved when the input is
driven differentially. The device may be driven single
ended. To drive the device in this manner, one of the
input pins must be capacitively coupled to ground. Use
a capacitor value large enough to allow for a lowimpedance path to ground at the lowest frequency of
operation. For operation down to 5MHz, a 0.001µF
capacitor is suggested.
Output Amplifiers
The output amplifiers are Class A differential amplifiers
capable of driving +61dBmV (QPSK, MAX3514) differentially. This architecture provides superior even-order
distortion performance but requires that a transformer
be used to convert to a single-ended output. In transmit-disable mode, the output amplifiers are powered
14
GND
*MAX3514/MAX3516 ONLY
down. A resistor is across the output so that the output
impedance remains matched when the amplifier is in
transmit-disable mode. Disabling the output devices
also results in low output noise.
MAX3514/MAX3516
To match the output impedance to a 75Ω load, the
transformer must have a turns ratio (voltage ratio) of 2:1
(4:1 impedance ratio). The differential amplifier is
biased directly from the +5V supply using the center
tap of the output transformer. This provides a significant benefit when switching between transmit mode
and transmit-disable mode. Stored energy due to bias
currents will cancel within the transformer and prevent
switching transients from reaching the load.
MAX3517
The MAX3517 uses external matching resistors to allow
matching to various load impedances through suitable
values of matching resistors and transformer turns
ratios.
Serial Interface
The serial interface has an active-low enable (CS) to
bracket the data, with data clocked in MSB first on the
rising edge of SCLK. Data is stored in the storage latch
on the rising edge of CS. The serial interface controls
______________________________________________________________________________________
Upstream CATV Amplifiers
Applications Information
High-Power and Low-Noise Modes
The MAX3514/MAX3516/MAX3517 have two transmit
modes, high power (HP) and low noise (LN). Each of
these modes is actuated by the high-order bit D7 of the
8-bit programming word. When D7 is a logic 1, HP
mode is enabled. When D7 is a logic 0, LN mode is
enabled.
Each of these modes is characterized by the activation
of a distinct output stage. In HP mode, the output stage
exhibits 15dB higher gain than LN mode. The lower
gain of the LN output stage allows for significantly lower
output noise and lower transmit/transmit-disable transients.
The full range of gain codes (D6–D0) may be used in
either mode. For DOCSIS applications, HP mode is recommended for output levels at or above +42dBmV
(MAX3514, D7 = 1, gain code = 87), LN mode when the
output level is below +42dBmV (MAX3514, D7 = 0, gain
code = 115).
Shutdown Mode
In normal operation, the shutdown pin (SHDN) is held
high. When SHDN is taken low, all circuits within the IC
are disabled. Only leakage currents flow in this state.
Data stored within the serial-data interface latches will
G
A
C
B
D
F
E
Table 1. Serial-Interface Control Word
BIT
MNEMONIC
MSB 7
D7
High-power/low-noise mode select
DESCRIPTION
6
D6
Gain code, bit 6
5
D5
Gain code, bit 5
4
D4
Gain code, bit 4
3
D3
Gain code, bit 3
2
D2
Gain code, bit 2
1
D1
Gain code, bit 1
LSB 0
D0
Gain code, bit 0
D7
D6
A. tSENS
B. tSDAS
C. tSDAH
D. tSCLKL
D5
D4
D3
D2
D1
D0
E. tSCLKH
F. tSENH
G. tDATAH/tDATAL
Figure 1. Serial-Interface Timing Diagram
Table 2. Chip State Control Bits
GAIN CODE
(DECIMAL)
GAIN*
(DB)
SHDN
TXEN
D7
D6
D5
D4
D3
D2
D1
D0
0
X
X
X
X
X
X
X
X
X
Shutdown Mode
1
0
X
X
X
X
X
X
X
X
Transmit-Disable Mode
1
1
1
X
X
X
X
X
X
X
Transmit-Enable Mode, High Power
1
1
0
X
X
X
X
X
X
X
STATES
Transmit- Enable Mode, Low Noise
48
-26
1
1
0
0
1
1
0
0
0
0
1
1
0
1
0
1
0
0
0
0
80
-10
1
1
0
1
1
1
0
0
1
1
115
8
9
1
1
1
1
0
1
0
1
1
1
87
1
1
1
1
1
0
1
1
1
0
110
20
1
1
1
1
1
1
1
1
0
1
125
28
*Typical Gain at +25°C, VCC = 5.0V
______________________________________________________________________________________
15
MAX3514/MAX3516/MAX3517
the state of the PGA and the output amplifiers. Tables 1
and 2 show the register format. Serial-interface timing is
shown in Figure 1.
MAX3514/MAX3516/MAX3517
Upstream CATV Amplifiers
be lost upon entering this mode. Current consumption
is reduced to 10µA (typ) in shutdown mode.
adequate balance between half-windings to achieve
substantial transient cancellation.
Output Match
Finally, keep in mind that transformer core inductance
varies proportionally with temperature. If the application
requires low temperature extremes (less than 0°C),
adequate primary inductance must be present to sustain low-frequency output capability as temperatures
drop. In general, this will not be a problem as modern
RF transformers have adequate bandwidth.
MAX3514/MAX3516
When used in conjunction with a 2:1 voltage-ratio transformer, the MAX3514/MAX3516 are internally resistively
matched to 75Ω. This internal resistor is across the
OUT+ and OUT- terminals.
To improve the match at the high end of the frequency
range (65MHz), a reactive match may be employed as
part of the ensuing diplex filter. A series inductor (typ
180nH) followed by a shunt capacitor (typ 33µF) can
be placed directly after the output transformer. This
match will also improve the gain flatness substantially.
As mentioned above, the matching components may be
incorporated into the diplex filter design. Optimize the
input impedance of the diplex filter to be 35 + j35 (typ) at
65MHz when using the specified output transformer.
MAX3517
The MAX3517 does not have an internal matching
resistor. This allows the device performance to be optimized for various load impedances.
When 300Ω resistors are placed across the output terminals of the device, performance identical to the
MAX3514 will result. If an impedance higher than 300Ω
is used, additional gain will result.
Note also that a 2:1 voltage-ratio output transformer is
not needed.
When operating the device with arbitrary output resistance and XFMR turns ratio, take care not to exceed the
allowable power dissipation (see Absolute Maximum
Ratings).
Transformer
To match the output of the MAX3514/MAX3516 to a 75Ω
load, a 2:1 voltage-ratio transformer is required. This
transformer must have adequate bandwidth to cover the
intended application. Note that most RF transformers
specify bandwidth with a 50Ω source on the primary and
a matching resistance on the secondary winding.
Operating in a 75Ω system will tend to shift the low-frequency edge of the transformer bandwidth specification
up by a factor of 1.5 due to primary inductance. Keep
this in mind when specifying a transformer.
Bias to the output stage is provided through the center
tap on the transformer primary. This greatly diminishes
the on/off transients present at the output when switching between transmit and transmit-disable modes.
Commercially available transformers typically have
16
Input Circuit
To achieve rated performance, the inputs of the
MAX3514/MAX3516/MAX3517 must be driven differentially with an appropriate input level. The differential
input impedance is approximately 1.5kΩ. Most applications will require a differential low-pass filter preceding
the device. The filter design will dictate a terminating
impedance of a specified value. Place this load impedance across the AC-coupled input pins (see Typical
Operating Circuit).
The MAX3514/MAX3517 have sufficient gain to produce an output level of +61dBmV (QPSK through a 2:1
transformer) when driven with a +34dBmV input signal.
The MAX3516 provides an additional 3dB of gain and
output level. When a lower input level is present, the
maximum output level will be reduced proportionally
and output linearity will increase. If an input level
greater than +34dBmV is used, the 3rd-order distortion
performance will degrade slightly.
If single-ended sources drive the MAX3514/MAX3516/
MAX3517, one of the input terminals must be capacitively coupled to ground (IN+ or IN-). The value of this
capacitor must be large enough to look like a short circuit at the lowest frequency of interest. For operation
at 5MHz with a 75Ω source impedance, a value of
0.001µF will suffice.
Layout Issues
A well-designed PC board is an essential part of an RF
circuit. For best performance, pay attention to powersupply layout issues, as well the output circuit layout.
Output Circuit Layout
The differential implementation of the MAX3514/
MAX3516/MAX3517s’ output has the benefit of significantly reducing even-order distortion, the most significant of which is 2nd-harmonic distortion. The degree of
distortion cancellation depends on the amplitude and
phase balance of the overall circuit. It is important to
keep the trace lengths from the output pins equal.
______________________________________________________________________________________
Upstream CATV Amplifiers
Ground inductance degrades distortion performance.
Therefore, ground plane connections to pin 4 and pin
20 should be made with multiple vias if necessary.
Exposed Paddle Thermal Considerations
The exposed paddle (EP) of the MAX3516’s 20-pin
TSSOP-EP package provides a low thermal-resistance
path to the die. It is important that the PC board on which
the MAX3516 is mounted, be designed to conduct heat
from this contact. In addition, the EP should be provided
with a low inductance path to electrical ground.
It is recommended that the EP be soldered to a ground
plane on the PC board, either directly or through an
array of plated via holes.
Typical Operating Circuit
12
CONTROL
LOGIC
SHDN
GND
TXEN
VCC
18
20
0.1µF
+5V
19
0.001µF
5
+
IN+
OUT+
2:1
16
OUTPUT
REXT*
INPUT
ANTI-ALIAS
FILTER
+5V
REXT*
6
+5V
0.1µF
0.001µF 2
4
3
7
1
IN-
MAX3514
MAX3516
MAX3517
OUT-
15
0.1µF
0.1µF
VCC
CEXT
14
**
GND
GND
GND
11
10
SCLK
GND
GND
SDA
CS
9
8
CONTROL
LOGIC
* MAX3517 ONLY
** MAX3514/MAX3516 ONLY
Chip Information
TRANSISTOR COUNT: 1006
______________________________________________________________________________________
17
MAX3514/MAX3516/MAX3517
Power-Supply Layout
For minimal coupling between different sections of the
IC, the ideal power-supply layout is a star configuration.
This configuration has a large-value decoupling capacitor at the central power-supply node. The power-supply traces branch out from this node, each going to a
separate power-supply node in the circuit. At the end of
each of these traces is a decoupling capacitor that provides a very low impedance at the frequency of interest. This arrangement provides local power-supply
decoupling at each power-supply pin.
The power-supply traces must be made as thick as
practical.
Upstream CATV Amplifiers
TSSOP.EPS
MAX3514/MAX3516/MAX3517
Package Information
18
______________________________________________________________________________________
Upstream CATV Amplifiers
QSOP.EPS
______________________________________________________________________________________
19
MAX3514/MAX3516/MAX3517
Package Information (continued)
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