19-1407; Rev 3; 8/99
SOT23, Rail-to-Rail, Fixed-Gain GainAmps/Open-Loop Op Amps
General Description Features
The MAX4174/MAX4175/MAX4274/MAX4275 Gain-
Amp™ family combines a low-cost Rail-to-Rail® op amp with precision internal gain-setting resistors and VCC / 2 biasing. Factory-trimmed on-chip resistors decrease design size, cost, and layout, and provide 0.1% gain accuracy. Fixed inverting gains from -0.25V/V to
-100V/V or noninverting gains from +1.25V/V to
+101V/V are available. These devices operate from a single +2.5V to +5.5V supply and consume only 300µA. GainAmp amplifiers are optimally compensated for each gain version, achieving exceptional GBW prod- ucts up to 23MHz (A V = +25V/V to +101V/V). High-volt- age fault protection withstands ±17V at either input without excessive current draw.
Three versions are available in this amplifier family: single/ dual/quad open-loop, unity-gain stable (MAX4281/ MAX4282/MAX4284); single/dual fixed gain (MAX4174/ MAX4274); and single/dual fixed gain plus internal VCC / 2 bias at the noninverting input (MAX4175/ MAX4275), which simplifies input biasing in single-supply designs. The input common-mode voltage range of the
GainAmp Family Provides Internal Precision Gain-Setting Resistors in SOT23 (MAX4174/5)
0.1% Gain Accuracy (RF/RG) (MAX4174/5, MAX4274/5)
54 Standard Gains Available (MAX4174/5, MAX4274/5)
Open-Loop Unity-Gain-Stable Op Amps (MAX4281/2/4)
Rail-to-Rail Outputs Drive 1k Load
Internal VCC / 2 Biasing (MAX4175/MAX4275)
♦ +2.5V to +5.5V Single Supply
300µA Supply Current
Up to 23MHz GBW Product
Fault-Protected Inputs Withstand ±17V
Stable with Capacitive Loads Up to 470pF with No Isolation Resistor
open-loop amplifiers extends from 150mV below the Ordering Information
PART* | TEMP. RANGE | PIN- PACKAGE | TOP MARK |
MAX4174_EUK-T | -40°C to +85°C | 5 SOT23-5 | †† |
MAX4175_EUK-T | -40°C to +85°C | 5 SOT23-5 | †† |
negative supply to within 1.2V of the positive supply. The outputs can swing rail-to-rail and drive a 1k load while maintaining excellent DC accuracy. The amplifier is stable for capacitive loads up to 470pF.
Applications
Portable Instruments Smart-Card Readers
Instruments, Terminals, Infrared Receivers for and Bar-Code Readers Remote Controls
Keyless Entry Low-Side Current-Sense
Photodiode Preamps Amplifiers
Ordering Information continued at end of data sheet.
* Insert the desired gain code (from the Gain Selection Guide) in the blank to complete the part number.
†† Refer to the Gain Selection Guide for a list of preferred gains and SOT Top Marks.
Selector Guide appears at end of data sheet.
IN+
RB MAX4175
VEE 2
+
RF
5 VCC
TOP VIEW
+5V
OUT 1
MAX4174
VCC
VCC
0.1F
IN+ 3
4 IN-
INPUT
IN-
VEE
SOT23-5
Pin Configurations continued at end of data sheet.
0.1F
RG
RF
VEE
OUT
RB
0.1F
RG
GainAmp is a trademark of Maxim Integrated Products. Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.
Maxim Integrated Products 1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769.
Supply Voltage (VCC to VEE) ....................................-0.3V to +6V
Voltage Inputs (IN_)
MAX4281/4282/4284.....................(VEE - 0.3V) to (VCC + 0.3V) MAX4174/4175/4274/4275 (with respect to GND) ...........±17V
Output Short-Circuit Duration (OUT_).....................................Continuous to Either VEE or VCC
Continuous Power Dissipation (TA = +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C).............571mW
8-Pin SO (derate 5.88mW/°C above +70°C).................471mW
8-Pin µMAX (derate 4.1mW/°C above +70°C) ............330mW
14-Pin SO (derate 8.3mW/°C above +70°C)...............667mW
16-Pin QSOP (derate 8.3mW/°C above +70°C)..........667mW Operating Temperature Range ...........................-40°C to +85°C
Maximum Junction Temperature .....................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
(VCC = +2.5V to +5.5V, VEE = 0, VIN+ = VIN- = VCC / 2, RL to VCC / 2, RL = open, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1)
PARAMETER | SYMBOL | CONDITIONS | MIN | TYP | MAX | UNITS | |
Supply Voltage Range | VCC | Guaranteed by PSRR tests | 2.5 | 5.5 | V | ||
Supply Current (per Amplifier) | ICC | MAX4174/MAX4274 | VCC = 3V | 300 | 460 | µA | |
VCC = 5V | 330 | 510 | |||||
MAX4175/MAX4275, includes VCC / 2 bias resistors | VCC = 3V | 320 | 480 | ||||
VCC = 5V | 355 | 530 | |||||
Input Offset Voltage | VOS | RL = 100k | ±0.5 | ±2.5 | mV | ||
Input Offset Voltage Drift | ±5 | µV/°C | |||||
Input Bias Current | IBIAS | IN_+, MAX4174/MAX4274 (Note 2) | ±0.05 | ±10 | nA | ||
Inverting Input Resistance | AV < 25V/V | 150 | k | ||||
AV > 25V/V | 40 | ||||||
Noninverting Input Resistance | MAX4174/MAX4274 | 1000 | M | ||||
MAX4175/MAX4275 | 75 | k | |||||
IN_+ Bias Voltage | MAX4175/MAX4275, VIN+ = VIN- | VCC / 2 - 0.25 | VCC / 2 + 0.25 | V | |||
IN_+ Input Voltage Range | Guaranteed by functional test (Note 3) | VEE | VCC - 1.2 | V | |||
IN_- Input Voltage Range | Guaranteed by functional test | VEE | VCC | V | |||
Power-Supply Rejection Ratio | PSRR | VCC = 2.5V to 5.5V | 70 | 90 | dB | ||
Closed-Loop Output Impedance | ROUT | 0.02 | | ||||
Short-Circuit Current | Shorted to VEE | 10 | mA | ||||
Shorted to VCC | 65 | ||||||
Output Voltage Swing (Note 4) | VOH/VOL | RL = 100k | VCC - VOH | 2 | 8 | mV | |
VOL - VEE | 2 | 8 | |||||
RL = 1k | VCC - VOH | 150 | 250 | ||||
VOL - VEE | 60 | 150 |
MAX4174/5, MAX4274/5, MAX4281/2/4
(VCC = +2.5V to +5.5V, VEE = 0, VIN+ = VIN- = VCC / 2, RL to VCC / 2, RL = open, TA = TMIN to TMAX, unless otherwise noted. Typical
PARAMETER | SYMBOL | CONDITIONS | MIN TYP MAX | UNITS |
Power-Up Time | Output settling to 1% | 1 | ms | |
Slew Rate | SR | VCC = 5V, VOUT = 4V step | 0.7 | V/µs |
Settling Time to Within 0.01% | VCC = 5V, VOUT = 4V step | 7 | µs | |
Input Noise Voltage Density | en | f = 10kHz (Note 5) | 90 | nV/Hz |
Input Noise Current Density | in | f = 10kHz | 4 | fA/Hz |
Capacitive Load Stability | CLOAD | No sustained oscillations | 470 | pF |
DC Gain Accuracy | (VEE + 25mV) < VOUT < (VCC - 25mV), RL = 100k (Note 6) | 0.1 0.5 | % | |
-3dB Bandwidth | BW-3dB | Gain = +1.25V/V | 1700 | kHz |
Gain = +3V/V | 970 | |||
Gain = +5V/V | 970 | |||
Gain = +10V/V | 640 | |||
Gain = +25V/V | 590 | |||
Gain = +51V/V | 330 |
(VCC = +2.5V to +5.5V, VEE = 0, VIN+ = VIN- = VCC / 2, RL to VCC / 2, RL = open, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1)
PARAMETER | SYMBOL | CONDITIONS | MIN TYP MAX | UNITS |
Supply Voltage Range | VCC | Guaranteed by PSRR tests | 2.5 5.5 | V |
Supply Current (per Amplifier) | ICC | VCC = 3V | 290 450 | µA |
VCC = 5V | 320 500 | µA | ||
Input Offset Voltage | VOS | RL = 100k | ±0.5 ±2 | mV |
Input Offset Voltage Drift | ±5 | µV/°C | ||
Input Bias Current | IBIAS | ±0.05 ±10 | nA | |
Input Offset Current | IOS | ±10 ±1000 | pA | |
Input Resistance | RIN | Differential or common mode | 1000 | M |
Input Capacitance | CIN | 2.5 | pF | |
Common-Mode Input Voltage Range | CMVR | Guaranteed by CMRR test | VEE - 0.15 VCC - 1.2 | V |
Common-Mode Rejection Ratio | CMRR | VEE - 0.15V VCM VCC - 1.2V | 60 90 | dB |
Power-Supply Rejection Ratio | PSRR | VCC = 2.5V to 5.5V | 70 90 | dB |
Closed-Loop Output Impedance | ROUT | AV = 1V/V | 0.02 | |
(VCC = +2.5V to +5.5V, VEE = 0, VIN+ = VIN- = VCC / 2, RL to VCC / 2, RL = open, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1)
PARAMETER | SYMBOL | CONDITIONS | MIN TYP MAX | UNITS | |
Short-Circuit Current | Shorted to VEE | 10 | mA | ||
Shorted to VCC | 65 | mA | |||
Large-Signal Voltage Gain | AVOL | VEE + 0.05V < VOUT < VCC - 0.1V, RL = 100k | 90 120 | dB | |
VEE + 0.25V < VOUT < VCC - 0.3V, RL = 1k | 80 100 | dB | |||
Output Voltage Swing | VOH/VOL | RL = 100k | VCC - VOH | 2 8 | mV |
VOL - VEE | 2 8 | ||||
RL = 1k | VCC - VOH | 160 250 | |||
VOL - VEE | 60 100 | ||||
Gain Bandwidth Product | GBW | 2 | MHz | ||
Slew Rate | SR | VCC = 5V, VOUT = 4V step | 0.7 | V/µs | |
Settling Time to within 0.01% | VCC = 5V, VOUT = 4V step | 7 | µs | ||
Input Noise Voltage Density | en | f = 10kHz | 60 | nV/Hz | |
Input Noise Current Density | in | f = 10kHz | 1.8 | fA/Hz | |
Capacitive Load Stability | CLOAD | No sustained oscillations, AV = 1V/V | 470 | pF | |
Power-Up Time | Output settling to 1% | 1 | ms |
Note 1: MAX4174/MAX4175/MAX4281 and MAX4274/MAX4275/MAX4282 and MAX4284 are 100% production tested at TA = +25°C. All temperature limits are guaranteed by design.
Note 2: Guaranteed by design.
Note 3: The input common-mode range for IN_+ is guaranteed by a functional test. A similar test is done on the IN_- input. See the
Applications Information section for more information on the input voltage range of the GainAmp. Note 4: For AV = -0.5V/V and AV = -0.25V/V, the output voltage swing is limited by the input voltage range. Note 5: Includes noise from on-chip resistors.
Note 6: The gain accuracy test is performed with the GainAmp in noninverting configuration. The output voltage swing is limited by the input voltage range for certain gains and supply voltage conditions. For situations where the output voltage swing is lim- ited by the valid input range, the output limits are adjusted accordingly.
Typical Operating Characteristics
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
LARGE-SIGNAL GAIN vs. FREQUENCY
AV = +1.25V/V | ||||||||||||||
AV = +2.25V/V | ||||||||||||||
4
3
NORMALIZED GAIN (dB)
2
1
0
-1
-2
-3
-4
-5
-6
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC01
AV = +2.5V/V | ||||||||||||||
AV = +4V/V | ||||||||||||||
4
3
NORMALIZED GAIN (dB)
2
1
0
-1
-2
-3
-4
-5
-6
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC02
MAX4174 TOC03
4
3
NORMALIZED GAIN (dB)
2 AV = +5V/V
1
0
-1
-2 AV = +9V/V
-3
-4
-5
-6
1k 10k
100k 1M
10M
1k 10k
100k 1M
10M
1k 10k
100k 1M
10M
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
LARGE-SIGNAL GAIN vs. FREQUENCY
4
3
NORMALIZED GAIN (dB)
2 AV = +10V/V
1
0
-1
/V
+2
=
V
A
-2 1V
-3
-4
-5
-6
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC04
4
3
NORMALIZED GAIN (dB)
2 AV = +25V/V
1
0
/V
50
+
V =
A
-1
-2 V
-3
-4
-5
-6
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC05
MAX4174 TOC06
4
3
NORMALIZED GAIN (dB)
2 AV = +51V/V
1
0
-1
AV = +100V/V
-2
-3
-4
-5
-6
1k 10k 100k 1M FREQUENCY (Hz)
10M
1k 10k 100k 1M FREQUENCY (Hz)
10M
1k 10k 100k 1M FREQUENCY (Hz)
10M
SMALL-SIGNAL GAIN vs. FREQUENCY
4
3
NORMALIZED GAIN (dB)
2 AV = +1.25V/V
1
0
-1
-2
-3
-4 AV = +2.25V/V
-5
-6
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC07
4
3
NORMALIZED GAIN (dB)
2 AV = +2.5V/V
1
0
/V
-1
-2 AV = +4V
-3
-4
-5
-6
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC08
MAX4174 TOC09
4
3
NORMALIZED GAIN (dB)
2 AV = +5V/V
1
0
-1
-2 AV = +9V/V
-3
-4
-5
-6
1k 10k 100k 1M FREQUENCY (Hz)
10M
1k 10k 100k 1M FREQUENCY (Hz)
10M
1k 10k 100k 1M FREQUENCY (Hz)
10M
SMALL-SIGNAL GAIN vs. FREQUENCY
4
3
NORMALIZED GAIN (dB)
2 AV = +10V/V
1
0
-1
-2
-3
-4 AV = +21V/V
-5
1k | 10k 100k 1M | 10M | 1k | 10k 100k 1M | 10M | 1k | 10k 100k 1M | 10M |
FREQUENCY (Hz) | FREQUENCY (Hz) | FREQUENCY (Hz) |
-6
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC10
4
3
NORMALIZED GAIN (dB)
2 AV = +25V/V
1
0
-1
-2
-3
-4 AV = +50V/V
-5
-6
SMALL-SIGNAL GAIN vs. FREQUENCY
MAX4174 TOC11
MAX4174 TOC12
4
3
NORMALIZED GAIN (dB)
2 AV = +51V/V
1
0
-1
-2
-3 AV = +100V/V
-4
-5
-6
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
0
-20
TOTAL HARMONIC DISTORTION vs. FREQUENCY
VOUT = 1Vp-p
0
-20
TOTAL HARMONIC DISTORTION vs. FREQUENCY
-p
MAX4174 TOC14
VOUT = 1Vp
THD (dB)
-40
-60
-80
AV = +10V/V
AV = +1.25V/V
-40
MAX4174 TOC13
THD (dB)
-60
-80
AV = +51V/V
-100
-120
-60
-70
THD (dB)
-80
-90
-100
-110
AV = +3V/V
1k 10k 100k 1M FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION vs. OUTPUT VOLTAGE SWING
MAX4174 TOC15
f = 10kHz
AV = +10V/V
AV = +1.25V/V AV = +3V/V
-100
-120
-60
-70
THD (dB)
-80
-90
-100
-110
AV = +25V/V
1k 10k 100k 1M FREQUENCY (Hz)
MAX4174 TOC16
TOTAL HARMONIC DISTORTION vs. OUTPUT VOLTAGE SWING
-120
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
VOLTAGE SWING (Vp-p)
-120
f = 10kHz | |||||||||
AV = +51V/V | |||||||||
AV = +25V/V | |||||||||
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
VOLTAGE SWING (Vp-p)
VOLTAGE NOISE DENSITY (nV/Hz)
1000
100
10
VOLTAGE NOISE DENSITY vs. FREQUENCY (AV = +1.25, +3, +10)
AV = +10V/V | |||||||||||||||
AV | = +3V/V | ||||||||||||||
AV = +1.25V/V | |||||||||||||||
MAX4174/5 toc 17
1 10 100 1k 10k 100k
1000
VOLTAGE NOISE DENSITY (nV/Hz)
100
10
VOLTAGE NOISE DENSITY vs. FREQUENCY (AV = +25, +51)
MAX4174/5 toc 18
AV = +25V/V
AV = +51V/V
INCLUDES RESISTOR NOISE
1 10 100 1k 10k 100k
CURRENT NOISE DENSITY vs.
FREQUENCY
CURRENT NOISE DENSITY (fA/Hz)
MAX4174/5 toc19
10
1
1 10 100 1k 10k 100k
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
MAX4174/5 toc 20
LARGE-SIGNAL PULSE RESPONSE
SMALL-SIGNAL PULSE RESPONSE
INPUT VOLTAGE
AV = +1.25V/V
OUTPUT
500mV/div
AV = +3V/V OUTPUT
50mV/div
AV = +5V/V OUTPUT
500mV/div
AV = +10V/V OUTPUT
500mV/div
AV = +25V/V OUTPUT
500mV/div
AV = +51V/V OUTPUT
500mV/div
INPUT VOLTAGE
MAX4174/5 toc 21
AV = +1.25V/V
OUTPUT
50mV/div
AV = +3V/V OUTPUT
50mV/div
AV = +5V/V OUTPUT
50mV/div
AV = +10V/V OUTPUT
50mV/div
AV = +25V/V OUTPUT
50mV/div
AV = +51V/V OUTPUT
50mV/div
CL = 0
2s/div
CL = 0
2s/div
PSR (dB)
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
-70
-75
-80
-85
-90
-95
POWER-SUPPLY REJECTION vs. FREQUENCY
MAX4174 TOC22
100
OUTPUT IMPEDANCE ()
10
1
0.1
0.01
OUTPUT IMPEDANCE vs. FREQUENCY
MAX4174 TOC23
5.0
4.9
4.8
VSWING (Vp-p)
4.7
4.6
4.5
4.4
4.3
4.2
4.1
MAX4174 TOC24
4.0
OUTPUT VOLTAGE SWING vs. RLOAD
100
1k 10k 100k 1M FREQUENCY (Hz)
100
1k 10k 100k 1M FREQUENCY (Hz)
1 10 100
RLOAD (k)
200
INPUT OFFSET VOLTAGE (V)
150
100
50
0
-50
-100
-150
MAX4174/5 toc 26
-200
INPUT OFFSET VOLTAGE vs.
MAX4174/5 toc 25
TEMPERATURE
VCC = 2.5V VCC = 5.5V
1000
INPUT BIAS CURRENT (pA)
800
600
400
200
0
-200
INPUT BIAS CURRENT vs. TEMPERATURE
VCC = 5.5V | ||||||||
VCC = 2.5V | ||||||||
-50
-35 -20
-5 10
25 40 55 70 85
-45
-30
-15
0 15 30 45 60 75 90
380
360
TEMPERATURE (°C)
MAX4174/5 toc 27
SUPPLY CURRENT vs. TEMPERATURE
VCC = 5.5V
VCC = 5V
VCC = 4V
100
80
60
VOH AND VOL vs. TEMPERATURE (VCC = 2.5V)
VOH, RL = 1k
VOH, RL = 100k
200
MAX4174/5 toc 28
180
160
140
TEMPERATURE (°C)
MAX4174/5 toc 29
VOH AND VOL vs. TEMPERATURE (VCC = 5.5V)
VOH, RL = 1k
SUPPLY CURRENT (A)
VOLTAGE (mV)
340
40 V
, R = 10k
120
320
OH L
20
0
100
VOLTAGE (mV)
80
60
VOH, RL = 100k VOH, RL = 10k V
, R = 100k
300
-20
VOL, RL = 100k
40
20
V , R = 10k
OL L
280
260
240
VCC = 3V
VCC = 2.5V
-40
-60
-80
-100
VOL, RL = 1k
OL L
0
-20
-40
-60
-80
-100
VOL, RL = 1k
VOL, RL = 100k
-50
-35
-20 -5
10 25 40 55 70 85
-50
-35
-20 -5 10
25 40 55 70 85
-50
-35
-20 -5 10
25 40 55 70 85
TEMPERATURE (°C)
TEMPERATURE (°C)
TEMPERATURE (°C)
(VCC = +5V, RL = 100k to VCC / 2, small-signal VOUT = 100mVp-p, large-signal VOUT = 1Vp-p, TA = +25°C, unless otherwise noted.)
160
140
120
100
OPEN-LOOP GAIN (dB)
80
60
40
20
0
-20
-40
OPEN-LOOP GAIN AND PHASE vs. FREQUENCY
MAX4174/5 toc30
4
3
2
PHASE (degrees)
1
GAIN (dB)
0
0 -1
-45 -2
-90
-135 -3
-180 -4
-225
-270 -5
-315 -6
SMALL-SIGNAL GAIN vs. FREQUENCY
LARGE-SIGNAL GAIN vs. FREQUENCY
MAX4174/5 toc31
MAX4174/5 toc32
4
3
2
1
GAIN (dB)
0
-1
-2
-3
-4
-5
-6
1 10
100 1k
10k
100k 1M
10M
1k 10k 100k 1M 10M
1k 10k 100k 1M 10M
0
-10
-20
-30
CMR (dB)
-40
-50
-60
-70
-80
-90
-100
FREQUENCY (Hz)
MAX4174/5 toc33
MAX4174/5 toc34
COMMON-MODE REJECTION vs. FREQUENCY
VOLTAGE NOISE DENSITY (nV/Hz)
1000
100
10
FREQUENCY (Hz)
VOLTAGE NOISE DENSITY vs. FREQUENCY
FREQUENCY (Hz)
CURRENT NOISE DENSITY vs. FREQUENCY
CURRENT NOISE DENSITY (fA/Hz)
MAX4174/5 toc35
10
1
100
1k 10k 100k FREQUENCY (Hz)
1M 10M
1 10 100 1k FREQUENCY (Hz)
10k 100k
1 10 100 1k FREQUENCY (Hz)
10k 100k
0
-10
-20
-30
-40
THD (dB)
-50
-60
-70
-80
-90
-100
-110
-120
TOTAL HARMONIC DISTORTION vs. FREQUENCY
AV = 1
VOUT = 1Vp-
p
-50
-55
-60
CROSSTALK (dB)
-65
-70
-75
-80
-85
-90
-95
MAX4282 CROSSTALK vs. FREQUENCY
MAX4284 CROSSTALK vs. FREQUENCY
MAX4174/5 toc37
MAX4174/5 toc38
-50 THREE AMPLIFIERS DRIVEN, ONE OUTPUT MEASURED
CROSSTALK (dB)
-55
-60
-65
-70
-75
MAX4174/5 toc36
1k 10k 100k 1M FREQUENCY (Hz)
1k 10k 100k FREQUENCY (Hz)
1M 10M
1k 10k 100k FREQUENCY (Hz)
1M 10M
PIN | NAME | FUNCTION | ||||||
MAX4281 | MAX4174/ MAX4175 | MAX4282 | MAX4274/ MAX4275 | MAX42 | 84 | |||
5 SOT23 | 8 SO | 5 SOT23 | 8 SO/µMAX | 8 SO/µMAX | 14 SO/TSSOP | 16 QSOP | NAME | FUNCTION |
1 | 6 | 1 | 1, 7 | 1, 7 | 1, 7, 8, 14 | 1, 7, 10, 16 | OUT, OUTA, OUTB, OUTC, OUTD | Amplifier Output |
2 | 4 | 2 | 4 | 4 | 11 | 13 | VEE | Negative Supply or Ground |
3 | 3 | 3 | 3, 5 | 3, 5 | 3, 5, 10, 12 | 3, 5, 12, 14 | IN+, INA+, INB+, INC+, IND+ | Noninverting Amplifier Input. Internally biased to VCC / 2 for MAX4175/MAX4275 |
4 | 2 | 4 | 2, 6 | 2, 6 | 2, 6, 9, 13 | 2, 6, 11, 15 | IN-, INA-, INB-, INC-, IND- | Inverting Amplifier Input. Connects to RG for MAX4174/ 4175/4274/4275. |
5 | 7 | 5 | 8 | 8 | 4 | 4 | VCC | Positive Supply |
— | 1, 5, 8 | — | — | — | — | 8, 9 | N.C. | No Connection. Not internally connected. |
IN-
VEE
RF
G
EE
R
V
IN-
RF
RG
IN+
OUT
OUT
MAX4175
MAX4174
IN+
MAX4281
VCC
VCC
VCC
VCC
IN+
RB 150k
IN-
RB
150k
OUT
VEE
VEE
Maxim’s GainAmp fixed-gain amplifiers combine a low- cost rail-to-rail op amp with internal gain-setting resis- tors. Factory-trimmed on-chip resistors provide 0.1% gain accuracy while decreasing design size, cost, and layout. Three versions are available in this amplifier family: single/dual/quad open-loop, unity-gain-stable devices (MAX4281/MAX4282/MAX4284); single/dual fixed-gain devices (MAX4174/MAX4274); and single/ dual devices with fixed gain plus internal V CC / 2 bias at the noninverting input (MAX4175/MAX4275). All amplifiers feature rail-to-rail outputs and drive a 1k load while maintaining excellent DC accuracy.
Open-Loop Op Amps The single/dual/quad MAX4281/MAX4282/MAX4284 are high-performance, open-loop op amps with rail-to- rail outputs. These devices are compensated for unity- gain stability, and feature a gain bandwidth (GBW) of 2MHz. The op amps in these ICs feature an input com- mon-mode range that extends from 150mV below the negative rail to within 1.2V of the positive rail. These high performance op amps serve as the core for this family of GainAmp fixed-gain amplifiers. Although the
-3dB bandwidth will not correspond to that of a fixed- gain amplifier in higher gain configurations, these open-loop op-amps can be used to prototype designs.
Internal Gain-Setting Resistors Maxim’s proprietary laser trimming techniques produce the necessary R F/RG values (Figure 1), so many gain offerings are easily available. These GainAmp fixed-gain amplifiers feature a negative-feedback resistor network that is laser trimmed to provide a gain-setting feedback ratio (R F/RG) with 0.1% typical accuracy. The standard op amp pinouts allow the GainAmp fixed-gain amplifiers to drop in directly to existing board designs, easily replacing op-amp-plus-resistor gain blocks.
GainAmp Bandwidth GainAmp fixed-gain amplifiers feature factory-trimmed precision resistors to provide fixed inverting gains from
-0.25V/V to -100V/V or noninverting gains from
+1.25V/V to +101V/V. The op-amp core is decompen- sated strategic ally over the gain-set options to maxi- mize bandwidth. Open-loop decompensation increases GBW product, ensuring that usable bandwidth is main- tained with increasing closed-loop gains. A GainAmp with a fixed gain of A V = 100V/V has a -3dB bandwidth of 230kHz. By comparison, a unity-gain-stable op amp configured for A V = 100V/V would yield a -3dB band- width of only 20kHz (Figure 2). Decompensation is per- formed at five intermediate gain sets, as shown in the Gain Selection Guide. Low gain decompensation great-
ly increases usable bandwidth, while decompensation above gains of +25V/V offers diminished returns.
VCC / 2 Internal Bias The MAX4175/MAX4275 GainAmp fixed-gain amplifiers with the V CC / 2 bias option are identical to standard GainAmp fixed-gain amplifiers, with the added feature of VCC / 2 internal bias at the noninverting inputs. Two 150k resistors form a voltage-divider for self-biasing the noninverting input, eliminating external bias resis- tors for AC-coupled applications, and allowing maxi- mum signal swing at the op amp’s rail-to-rail output for single-supply systems (see Typical Operating Circuit ). For DC-coupled applications, use the MAX4174/ MAX4274.
High-Voltage (±17V) Input Fault Protection
The MAX4174/MAX4175/MAX4274/MAX4275 include
RG
RG
±17V input fault protection. For normal operation, see the input voltage range specification in the Electrical Characteristics. Overdriven inputs up to ±17V will not
VCC
AV = -RF
IN-
RG
RF
AV = 1 + RF
VEE
OUT
IN+
20kHz
230kHz
GAIN (dB)
Figure 1. Internal Gain-Setting Resistors
60
50
40
-3dB
30
MAX4281, AV = 100 2MHz GBW
MAX4174, AV = 100 23MHz GBW
20
10
0
10 100 1k 10k 100k 1M 10M
FREQUENCY (Hz)
Figure 2. Gain-Bandwidth Comparison
cause output phase reversal. A back-to-back SCR structure at the input pins allows either input to safely swing ±17V relative to V EE (Figure 3). Additionally, the internal op-amp inputs are diode clamped to either supply rail for the protection of sensitive input stage cir- cuitry. Current through the clamp diodes is limited by a 5k resistor at the noninverting input, and by R G at the inverting input. An IN+ or IN- fault voltage as high as
±17V will cause less than 3.5mA of current to flow through the input pin, protecting both the GainAmp and the signal source from damage.
GainAmp fixed-gain amplifiers offer a precision, fixed gain amplifier in a small package that can be used in a variety of circuit board designs. GainAmp fixed-gain amplifiers can be used in many op amp circuits that use resistive negative feedback to set gain, and that do not require other connections to the op-amp inverting input. Both inverting and noninverting op-amp configurations can be implemented easily using a GainAmp.
GainAmp Input Voltage Range
The MAX4174/MAX4175/MAX4274/MAX4275 combine
both an op amp and gain-setting feedback resistors on the same chip. Because the inverting input pin is actu- ally tied to the R G input series resistor, the inverting input voltage range is different from the noninverting input voltage range. Just as with a discrete design, care must be taken not to saturate the inputs/output of the core op amp, to avoid signal distortions or clipping.
The inverting inputs (IN_-) of the MAX4174/MAX4175/ MAX4274/MAX4275 must be within the supply rails or signal distortion may result. The GainAmp’s inverting input structure includes diodes to both supplies, such that driving the inverting input beyond the rails may cause signal distortions (Figure 1). For applications that require sensing voltages beyond the rails, use the MAX4281/MAX4282/MAX4284 open-loop op amps (Figure 4).
RF
IN-
RG
17V SCR
VEE
VCC
VCC
MAX4174 MAX4175 MAX4274 MAX4275
OUT
IN+
5k
17V SCR
VEE
VEE
VEE
NOTE: INPUT STAGE PROTECTION INCLUDES
TWO 17V SCRs AND TWO DIODES AT THE INPUT STAGE.
BIAS RESISTORS (MAX4175/MAX4275 ONLY)
Figure 3. Input Protection
MAX4281
VCC
VCC
MAX4175
RB
VCC
0.1F
RB
V = - V
RG
)
VIN
RG
RF
VOUT = -RF (VIN)
VIN
RG
RF
RG
VOUT = VIN (1+ RF )
VIN
RG
VOUT = - VIN ( RF )
2
F
R
IN (
OUT
VCC
RG
Figure 4. Single-Supply, DC-Coupled Inverting Amplifier with Negative Input Voltage
Figure 6. Single-Supply, AC-Coupled Inverting Amplifier
MAX4174
VCC
VCC
MAX4174
VIN
VEE
VEE
RF
RG
RF
RG
Figure 5. Dual-Supply, DC-Coupled Inverting Amplifier
GainAmp Signal Coupling and Configurations
Common op-amp configurations include both nonin- verting and inverting amplifiers. Figures 5–8 show vari- ous single and dual-supply circuit configurations. Single-supply systems benefit from a midsupply bias on the noninverting input (provided internally on MAX4175/MAX4275), as this produces a quiescent DC level at the center of the rail-to-rail output stage signal swing. For dual-supply systems, ground-referenced signals may be DC-coupled into the inverting or non- inverting inputs.
Figure 7. Dual-Supply, AC-Coupled Noninverting Amplifier
IN_+ Filter on MAX4175/MAX4275 Internal resistor biasing of the VCC / 2 bias options cou- ples power-supply noise directly to the op amp’s nonin- verting input. To minimize high-frequency power-supply noise coupling, add a 1µF to 0.1µF capacitor from IN+ to ground to create a lowpass filter (Figure 6). The low- pass filter resulting from the internal bias resistors and added capacitor can help eliminate higher frequency power-supply noise coupling through the noninverting input.
Supply Bypassing and Board Layout All devices in the GainAmp family operate from a +2.5V to +5.5V single supply or from ±1.25V to ±2.75V dual supplies. For single-supply operation, bypass the power supply with a 0.1µF capacitor to ground. For dual supplies, bypass each supply to ground. Bypass with capacitors as close to the device as possible, to min- imize lead inductance and noise. A printed circuit board with a low-inductance ground plane is recommended.
RG
Capacitive-Load Stability Driving large capacitive loads can cause instability in most low-power, rail-to-rail output amplifiers. The fixed-
gain amplifiers of this GainAmp family are stable with capacitive loads up to 470pF. Stability with higher capacitive loads can be improved by adding an isolation resistor in series with the op-amp output, as shown in Figure 9. This resistor improves the circuit’s phase mar- gin by isolating the load capacitor from the amplifier’s output. In Figure 10, a 1000pF capacitor is driven with a 100 isolation resistor exhibiting some overshoot but no oscillation. Figures 11 and 12 show the typical small-sig- nal pulse responses of GainAmp fixed-gain amplifiers with 250pF and 470pF capacitive loads and no isolation resistor.
VCC
MAX4174
INPUT
VIN
VOUT = VIN (1+ RF )
AV = +5V/V
50mV/div
OUTPUT
RG
OUTPUT
AV = +5V/V
500mV/div
VEE
RF
Figure 8. Dual-Supply, DC-Coupled Noninverting Amplifier
Figure 10. Small-Signal/Large-Signal Transient Response with Excessive Capacitive Load with Isolation Resistor
MAX4174
RG
RF
VCC
RISO
OUTPUT
INPUT
CL
RL
VEE
Figure 9. Dual-Supply, Capacitive-Load Driving Circuit
INPUT
AV = +1.25V/V
OUTPUT
50mV/div
AV = +3V/V OUTPUT
50mV/div
AV = +5V/V OUTPUT
50mV/div
AV = +10V/V OUTPUT
50mV/div
AV = +25V/V OUTPUT
50mV/div
AV = +51V/V OUTPUT
50mV/div
2s/div
INPUT
AV = +1.25V/V
OUTPUT
50mV/div
AV = +3V/V OUTPUT
50mV/div
AV = +5V/V OUTPUT
50mV/div
AV = +10V/V OUTPUT
50mV/div
AV = +25V/V OUTPUT
50mV/div
AV = +51V/V OUTPUT
50mV/div
2s/div
Figure 11. MAX4174/MAX4175 Small-Signal Pulse Response (CL = 250pF, RL = 100k)
Figure 12. MAX4174/MAX4175 Small-Signal Pulse Response (CL = 470pF, RL = 100k)
GAIN CODE | RF/RG INVERTING GAIN | 1+ (RF/RG) NONINVERTING GAIN | -3dB BW (kHz)† | TOP MARK | |
MAX4174 | MAX4175 | ||||
AB* | 0.25 | 1.25 | 1700 | ACDS | ACET |
AC | 0.5 | 1.5 | 1280 | ACDT | ACEU |
AD* | 1 | 2 | 590 | ACDU | ACEV |
AE | 1.25 | 2.25 | 450 | ACDV | ACEW |
AF | 1.5 | 2.5 | 1180 | ACDW | ACEX |
AG* | 2 | 3 | 970 | ACDX | ACEY |
AH | 2.5 | 3.5 | 820 | ACDY | ACEZ |
AJ | 3 | 4 | 690 | ACDZ | ACFA |
AK* | 4 | 5 | 970 | ACEA | ACFB |
AL | 5 | 6 | 790 | ACEB | ACFC |
AM | 6 | 7 | 640 | ACEC | ACFD |
AN | 8 | 9 | 480 | ACED | ACFE |
AO* | 9 | 10 | 640 | ACEE | ACFF |
BA* | 10 | 11 | 560 | ACEF | ACFG |
BB | 12.5 | 13.5 | 460 | ACEG | ACFH |
BC | 15 | 16 | 390 | ACEH | ACFI |
BD | 20 | 21 | 300 | ACEI | ACFJ |
BE* | 24 | 25 | 590 | ACEJ | ACFK |
BF | 25 | 26 | 580 | ACEK | ACFL |
BG | 30 | 31 | 510 | ACEL | ACFM |
BH | 40 | 41 | 390 | ACEM | ACFN |
BJ* | 49 | 50 | 310 | ACEN | ACFO |
BK* | 50 | 51 | 330 | ACEO | ACFP |
BL | 60 | 61 | 310 | ACEP | ACFQ |
BM | 80 | 81 | 260 | ACEQ | ACFR |
BN* | 99 | 100 | 230 | ACER | ACFS |
CA* | 100 | 101 | 230 | ACES | ACFT |
Note: Gains in the noninverting configuration are 1+ (RF/RG) and range from +1.25V/V to +101V/V. For a +1V/V gain, use the MAX4281/MAX4282/MAX4284.
* Preferred Gains. These gain versions are available as samples and in small quantities.
† The -3dB bandwidth is the same for inverting and noninverting configurations.
TOP VIEW
OUT 1
MAX4175
5 VCC
MAX4281
5
1
OUT VCC
VEE 2
IN+ 3
+ - RF
R RG
R
VCC 4
VEE
IN+
+ -
4
3
2
IN-
SOT23-5 SOT23-5
N.C.
IN-
MAX4281
1
2
N.C.
7
8
VCC
OUTA 1
INA- 2
MAX4282
8 VCC
7 OUTB
OUTA 1
INA- 2
MAX4274
8
RF
7
RG RF
VCC
OUTB
3
IN+
6
OUT
INA+ 3
+ -
6 INB-
INA+ 3
+ -
6 INB-
RG
VEE
N.C.
5
4
SO
VEE 4
MAX/SO
5 INB+
VEE 4
MAX/SO
5 INB+
OUTA 1
INA- 2
MAX4275
RF RG
VCC RF
+ -
8 VCC
7 OUTB
OUTA 1
INA- 2
INA+ 3
MAX4284
+ -
14 OUTD
13 IND-
12 IND+
OUTA 1
INA- 2
INA+ 3
MAX4284
+ -
16 OUTD
15 IND-
14 IND+
R RG
INA+ 3
R
6
VCC
INB-
VCC 4
11 VEE
VCC 4
13 VEE
+ -
VEE 4
R R
5 INB+
INB+ 5
10 INC+
INB+ 5
12 INC+
MAX/SO
INB- 6
OUTB 7
SO/TSSOP
9 INC-
8 OUTC
INB- 6
OUTB 7
N.C. 8
11 INC-
+ -
10 OUTC
9 N.C.
QSOP
PART* | TEMP. RANGE | PIN- PACKAGE | TOP MARK |
MAX4274_EUA | -40°C to +85°C | 8 µMAX | — |
MAX4274_ESA | -40°C to +85°C | 8 SO | — |
MAX4275_EUA | -40°C to +85°C | 8 µMAX | — |
MAX4275_ESA | -40°C to +85°C | 8 SO | — |
MAX4281EUK-T | -40°C to +85°C | 5 SOT23-5 | ACDR |
MAX4281ESA | -40°C to +85°C | 8 SO | — |
MAX4282EUA | -40°C to +85°C | 8 µMAX | — |
MAX4282ESA | -40°C to +85°C | 8 SO | — |
MAX4284EUD | -40°C to +85°C | 14 TSSOP | — |
MAX4284ESD | -40°C to +85°C | 14 SO | — |
MAX4284EEE | -40°C to +85°C | 16 QSOP | — |
TRANSISTOR COUNTS:
MAX4174: 178
MAX4175: 178
MAX4274: 332
MAX4275: 332
MAX4281: 178
MAX4282: 332
MAX4284: 328 SUBSTRATE CONNECTED TO VEE
Note: Refer to Gain Selection Guide for SOT top marks.
*Insert the desired gain code (from the Gain Selection Guide) in the blank to complete the part number. Refer to Gain Selection Guide for a list of preferred gains.
PART* | INVERTING GAINS AVAILABLE (V/V) (INVERTING, RF/RG) | NONINVERTING GAIN (V/V) | INTERNAL RESISTORS | INTERNAL VCC/2 BIAS | NO. OF AMPS PER PACKAGE | PIN-PACKAGE | |
MAX4174_ | -0.25 to -100 | +1.25 to +101 | Yes | No | 1 | 5-pin SOT23 | |
MAX4175_ | -0.25 to -100 | +1.25 to +101 | Yes | Yes | 1 | 5-pin SOT23 | |
MAX4274_ | -0.25 to -100 | +1.25 to +101 | Yes | No | 2 | 8-pin µMAX/SO | |
MAX4275_ | -0.25 to -100 | +1.25 to +101 | Yes | Yes | 2 | 8-pin µMAX/SO | |
MAX4281_ | Open Loop, Unity-Gain Stable | No | No | 1 | 5-pin SOT23, 8-pin SO | ||
MAX4282_ | Open Loop, Unity-Gain Stable | No | No | 2 | 8-pin µMAX/SO | ||
MAX4284_ | Open Loop, Unity-Gain Stable | No | No | 4 | 14-pin SO/TSSOP, 16-pin QSOP |
* Insert the desired gain code (from the Gain Selection Guide) in the blank to complete the part number.
SOT5L.EPS
8LUMAXD.EPS
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circu it patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
20 Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1999 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Maxim Integrated:
MAX4014EUK+T MAX4281ESA+ MAX4281ESA+T MAX4281EUK+T MAX4282ESA MAX4282ESA+ MAX4282ESA+T MAX4282EUA+ MAX4282EUA+T MAX4284EEE MAX4284ESD MAX4284EEE-T MAX4284ESD-T