AVAILABLE
Functional Diagrams
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
General Description
The MAX4475–MAX4478/MAX4488/MAX4489 wide-
band, low-noise, low-distortion operational amplifiers
offer rail-to-rail outputs and single-supply operation
down to 2.7V. They draw 2.2mA of quiescent supply
current per amplifier while featuring ultra-low distortion
(0.0002% THD+N), as well as low input voltage-noise
density (4.5nV/Hz) and low input current-noise density
(0.5fA/Hz). These features make the devices an ideal
choice for applications that require low distortion and/or
low noise.
For power conservation, the MAX4475/MAX4488 offer a
low-power shutdown mode that reduces supply current
to 0.01µA and places the amplifiers’ outputs into a high-
impedance state. These amplifiers have outputs which
swing rail-to-rail and their input common-mode voltage
range includes ground. The MAX4475–MAX4478 are
unity-gain stable with a gain-bandwidth product of
10MHz. The MAX4488/4489 are internally compensated
for gains of +5V/V or greater with a gain-bandwidth
product of 42MHz. The single MAX4475/MAX4476/
MAX4488 are available in space-saving, 6-pin SOT23
and TDFN packages.
Applications
ADC Buffers
DAC Output Amplifiers
Low-Noise Microphone/Preamplifiers
Digital Scales
Strain Gauges/Sensor Amplifiers
Medical Instrumentation
Features
oLow Input Voltage-Noise Density: 4.5nV/√Hz
oLow Input Current-Noise Density: 0.5fA/√Hz
oLow Distortion: 0.0002% THD+N (1kΩ load)
oSingle-Supply Operation from +2.7V to +5.5V
oInput Common-Mode Voltage Range Includes
Ground
oRail-to-Rail Output Swings with a 1kΩ Load
o10MHz GBW Product, Unity-Gain Stable
(MAX4475–MAX4478)
o42MHz GBW Product, Stable with AV +5V/V
(MAX4488/MAX4489)
oExcellent DC Characteristics
VOS = 70µV
IBIAS = 1pA
Large-Signal Voltage Gain = 120dB
oLow-Power Shutdown Mode:
Reduces Supply Current to 0.01µA
Places Output in High-Impedance State
oAvailable in Space-Saving SOT23, TDFN, µMAX®,
and TSSOP Packages
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Ordering Information
Selector Guide
Ordering Information continued at end of data sheet.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
*
EP = Exposed pad (connect to VSS).
/V denotes an automotive qualified part.
T = Tape and reel.
Pin Configurations and Typical Operating Circuit appear at
end of data sheet.
PART TEMP RANGE PIN-
PACKAGE
TOP
MARK
MAX4475AUT+T -40°C to +125°C 6 SOT23 AAZV
MAX4475AUA+ -40°C to +125°C 8 µMAX
MAX4475ASA+ -40°C to +125°C 8 SO
MAX4475ATT+T -40°C to +125°C 6 TDFN-EP* +ADD
MAX4475AUT/V+T -40°C to +125°C 6 SOT23 +ACQQ
PART G A IN B W
( M H z)
STABLE
GAIN
(V/V)
NO. OF
AMPS SHDN
MAX4475 10 1 1 Yes
MAX4476 10 1 1
MAX4477 10 1 2
MAX4478 10 1 4
MAX4488 42 5 1 Yes
MAX4489 42 5 2
25
20
10
5
0
10 1k 10k100 100k
INPUT VOLTAGE-NOISE DENSITY
vs. FREQUENCY
MAX4475 toc20
FREQUENCY (Hz)
15
VIN EQUIVALENT INPUT NOISE VOLTAGE (nV/Hz)
Typical Operating Characteristic
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Selector Guide
19-2137; Rev 5; 7/10
Ordering Information continued at end of data sheet.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
*
EP = Exposed pad (connect to VSS).
/V denotes an automotive qualified part.
T = Tape and reel.
Pin Configurations and Typical Operating Circuit appear at
end of data sheet.
MAX4475–MAX4478/
MAX4488/MAX4489
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
ABSOLUTE MAXIMUM RATINGS
DC ELECTRICAL CHARACTERISTICS
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= -40°C to +125°C, unless otherwise noted.
Typical values are at TA= +25°C.) (Notes 1, 2)
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.
Power-Supply Voltage (VDD to VSS) ......................-0.3V to +6.0V
Analog Input Voltage (IN_+, IN_-)....(VSS - 0.3V) to (VDD + 0.3V)
SHDN Input Voltage....................................(VSS - 0.3V) to +6.0V
Output Short-Circuit Duration to Either Supply ..........Continuous
Continuous Input Current (IN+, IN-) .................................±10mA
Continuous Power Dissipation (TA= +70°C)
6-Pin SOT23 (derate 9.1mW/°C above +70°C)...........727mW
6-Pin TDFN (derate 18.2mW/°C above 70°C)...........1454mW
8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW
8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW
14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW
14-Pin TSSOP (derate 9.1mW/°C above +70°C) .........727mW
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow)
SOT23, µMAX, TSSOP, TDFN, and 8-Pin SO...............+260°C
14-Pin SO.....................................................................+240°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Supply Voltage Range VDD (Note 3) 2.7 5.5 V
VDD = 3V 2.2
Normal mode VDD = 5V 2.5 4.4 mA
Quiescent Supply Current Per
Amplifier ID
Shutdown mode (SHDN = VSS) (Note 2) 0.01 1.0 µA
TA = +25°C ±70 ±350
Input Offset Voltage VOS TA = -40°C to +125°C ±750 µV
Input Offset Voltage Tempco TCVOS ±0.3 ±6 µV/°C
Input Bias Current IB(Note 4) ±1 ±150 pA
Input Offset Current IOS (Note 4) ±1 ±150 pA
Differential Input Resistance RIN 1000 G
TA = +25°C-0.2V
D D - 1.6
Input Common-Mode Voltage
Range VCM Guaranteed by
CMRR Test TA = -40°C to +125°C-0.1 V
D D - 1.7 V
(VSS - 0.2V)
VCM (VDD -
1.6V)
TA = +25°C 90 115
Common-Mode Rejection Ratio CMRR (VSS - 0.1V)
VCM (VDD -
1.7V)
TA = -40°C to +125°C90
dB
Power-Supply Rejection Ratio PSRR VDD = 2.7 to 5.5V 90 120 dB
RL = 10k to VDD/2;
VOUT = 100mV to (VDD - 125mV) 90 120
RL = 1k to VDD/2;
VOUT = 200mV to (VDD - 250mV) 85 110
Large-Signal Voltage Gain AVOL
RL = 500 to VDD/2;
VOUT = 350mV to (VDD - 500mV) 85 110
dB
MAX4475–MAX4478/
MAX4488/MAX4489
2
Maxim Integrated
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
DC ELECTRICAL CHARACTERISTICS (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= -40°C to +125°C, unless otherwise noted.
Typical values are at TA= +25°C.) (Notes 1, 2)
AC ELECTRICAL CHARACTERISTICS
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
VDD - VOH 10 45
|VIN+ - VIN-| 10mV,
RL = 10k to VDD/2 VOL - VSS 10 40
VDD - VOH 80 200
|VIN+ - VIN-| 10mV,
RL = 1k to VDD/2 VOL - VSS 50 150
VDD - VOH 100 300
Output Voltage Swing VOUT
|VIN+ - VIN-| 10mV,
RL = 500 to VDD/2 VOL - VSS 80 250
mV
Output Short-Circuit Current ISC 48 mA
Output Leakage Current ILEAK Shutdown mode (SHDN = VSS),
VOUT = VSS to VDD ±0.001 ±1.0 µA
SHDN Logic Low VIL 0.3 x V
D D V
SHDN Logic High VIH 0.7 x VDD V
SHDN Input Current SHDN = VSS to VDD 0.01 1 µA
Input Capacitance CIN 10 pF
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
MAX4475–MAX4478 A
V
= +1V/V 10
Gain-Bandwidth Product GBWP MAX4488/MAX4489 A
V
= +5V/V 42 MHz
MAX4475–MAX4478 A
V
= +1V/V 3
Slew Rate SR MAX4488/MAX4489 A
V
= +5V/V 10 V/µs
MAX4475–MAX4478 A
V
= +1V/V 0.4
Full-Power Bandwidth (Note 5) MAX4488/MAX4489 A
V
= +5V/V 1.25 MHz
Peak-to-Peak Input Noise Voltage e
n
-
f = 0.1Hz to 10Hz 260 nV
P-P
f = 10Hz 21
f = 1kHz 4.5
Input Voltage-Noise Density e
n
f = 30kHz 3.5
nV/Hz
Input Current-Noise Density i
n
f = 1kHz 0.5 fA/Hz
f = 1kHz 0.0002
V
OUT
= 2V
P-P
,
A
V
= +1V/V
(MAX4475–MAX4478),
R
L
= 10k to GND f = 20kHz 0.0007
f = 1kHz 0.0002
V
OUT
= 2V
P-P
,
A
V
= +1V/V
(MAX4475–MAX4478),
R
L
= 1k to GND f = 20kHz 0.001
f = 1kHz 0.0004
Total Harmonic Distortion Plus
Noise (Note 6) THD + N
V
OUT
= 2V
P-P
,
A
V
= +5V/V
(MAX4488/MAX4489),
R
L
= 10k to GND f = 20kHz 0.0006
%
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
3
4
2
10
8
6
12
14
16
18
-50 -30 -20-40 -100 1020304050
INPUT OFFSET VOLTAGE DISTRIBUTION
MAX4475-8 toc1
VOS (µV)
PERCENTAGE OF UNITS (%)
0
-250
-100
-150
-200
0
-50
200
150
100
50
250
-50 -25 0 25 50 75 100 125
OFFSET VOLTAGE vs. TEMPERATURE
MAX4475 toc02
TEMPERATURE (°C)
INPUT OFFSET VOLTAGE (µV)
VCOM = 0V
0
10
30
20
40
50
-0.5 1.50.5 2.5 3.5 4.5
INPUT OFFSET VOLTAGE
vs. INPUT COMMON-MODE VOLTAGE
MAX4475 toc03
INPUT COMMON-MODE VOLTAGE (V)
INPUT OFFSET VOLTAGE (µV)
VDD = 3V
VDD = 5V
Typical Operating Characteristics
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, input noise floor of test equipment =10nV/Hz for all distortion
measurements, TA= +25°C, unless otherwise noted.)
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Note 1: All devices are 100% tested at TA= +25°C. Limits over temperature are guaranteed by design.
Note 2: SHDN is available on the MAX4475/MAX4488 only.
Note 3: Guaranteed by the PSRR test.
Note 4: Guaranteed by design.
Note 5: Full-power bandwidth for unity-gain stable devices (MAX4475–MAX4478) is measured in a closed-loop gain of +2V/V to
accommodate the input voltage range, VOUT = 4VP-P.
Note 6: Lowpass-filter bandwidth is 22kHz for f = 1kHz and 80kHz for f = 20kHz. Noise floor of test equipment = 10nV/Hz.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
f = 1kHz 0.0005
Total Harmonic Distortion Plus
Noise (Note 6) THD + N
VOUT = 2VP-P,
AV = +5V/V
(MAX4488/MAX4489),
RL = 1k to GND f = 20kHz 0.008
%
Capacitive-Load Stability No sustained oscillations 200 pF
Gain Margin GM 12 dB
MAX4475–MAX4478, AV = +1V/V 70
Phase Margin ΦMMAX4488/MAX4489, AV = +5V/V 80 degrees
Settling Time To 0.01%, VOUT = 2V step 2 µs
Delay Time to Shutdown tSH 1.5 µs
Enable Delay Time from Shutdown tEN VOUT = 2.5V, VOUT settles to 0.1% 10 µs
Power-Up Delay Time VDD = 0 to 5V step, VOUT stable to 0.1% 13 µs
AC ELECTRICAL CHARACTERISTICS (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= +25°C.)
MAX4475–MAX4478/
MAX4488/MAX4489
4
Maxim Integrated
Typical Operating Characteristics (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, input noise floor of test equipment =10nV/Hz for all distortion
measurements, TA= +25°C, unless otherwise noted.)
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
0
0.05
0.10
0.15
0.20
0.25
045231678910
OUTPUT VOLTAGE
vs. OUTPUT LOAD CURRENT
MAX4475 toc04
OUTPUT LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
VDD - VOH
VOL
VDD = 3V OR 5V
VDIFF = ±10mV
0
20
10
40
30
60
50
70
-50 0 25-25 50 75 100 125
OUTPUT VOLTAGE SWING (VOH)
vs. TEMPERATURE
MAX4475 toc05
TEMPERATURE (°C)
VDD - VOH (mV)
RL = 1k
RL = 10k
0
20
10
40
30
60
50
70
-50 0 25-25 50 75 100 125
OUTPUT VOLTAGE SWING (VOL)
vs. TEMPERATURE
MAX4475 toc06
TEMPERATURE (°C)
VOL (mV)
RL = 1k
RL = 10k
50
60
70
80
90
100
110
120
130
0 50 100 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4475 toc07
VOUT SWING FROM EITHER SUPPLY (mV)
AV (dB)
RL = 200kRL = 20kRL = 2k
VDD = 3V
RL REFERENCED TO GND
50
60
70
80
90
100
110
120
130
0 50 100 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4475 toc08
VOUT SWING FROM EITHER SUPPLY (mV)
AV (dB)
RL = 200kRL = 20k
RL = 2k
VDD = 3V
RL REFERENCED TO VDD
50
60
70
80
90
100
110
120
130
0 50 100 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4475 toc09
VOUT SWING FROM EITHER SUPPLY (mV)
AV (dB)
RL = 200k
RL = 20k
RL = 2k
VDD = 5V
RL REFERENCED TO GND
50
60
70
80
90
100
110
120
130
0 50 100 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4475 toc10
VOUT SWING FROM EITHER SUPPLY (mV)
AV (dB)
RL = 200k
RL = 2k
RL = 20k
VDD = 5V
RL REFERENCED TO VDD
50
70
60
100
90
80
130
120
110
140
-50 0 25-25 50 75 100 125
LARGE-SIGNAL VOLTAGE GAIN
vs. TEMPERATURE
MAX4475 toc11
TEMPERATURE (°C)
AVOL (dB)
RL = 100k
RL = 10k
VOUT = 150mV TO 4.75V
0
1.0
0.5
2.0
1.5
2.5
3.0
-50 25 50-25 0 75 100 125
SUPPLY CURRENT vs. TEMPERATURE
MAX4475 toc12
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
PER AMPLIFIER
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
5
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Typical Operating Characteristics (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, input noise floor of test equipment =10nV/Hz for all distortion
measurements, TA= +25°C, unless otherwise noted.)
0
1.0
0.5
2.0
1.5
2.5
3.0
2.5 3.5 4.03.0 4.5 5.0 5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX4475 toc13
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
PER AMPLIFIER
0
1.0
0.5
2.0
1.5
2.5
3.0
021345
SUPPLY CURRENT vs. OUTPUT VOLTAGE
MAX4475 toc14
OUTPUT VOLTAGE (V)
SUPPLY CURRENT (mA)
VDD = 5V
VDD = 3V
-20
-15
-10
-5
0
5
10
15
20
2.5 3.53.0 4.0 4.5 5.0 5.5
INPUT OFFSET VOLTAGE
vs. SUPPLY VOLTAGE
MAX4475 toc15
SUPPLY VOLTAGE (V)
INPUT OFFSET VOLTAGE (µV)
MAX4475–MAX4478
GAIN AND PHASE vs. FREQUENCY
INPUT FREQUENCY (Hz)
100 100k 1M 10M1k 10k 100M
GAIN (dB)
60
-40
-30
-20
-10
0
10
20
50
40
30
-180
PHASE (degrees)
180
-144
-108
-72
-36
0
36
144
108
72
MAX4475 toc16
VDD = 3V OR 5V
RL = 50k
CL = 20pF
AV = +1000V/V
GAIN
PHASE
MAX4488/MAX4489
GAIN AND PHASE vs. FREQUENCY
INPUT FREQUENCY (Hz)
100 100k 1M 10M1k 10k 100M
GAIN (dB)
60
-40
-30
-20
-10
0
10
20
50
40
30
-180
PHASE (degrees)
180
-144
-108
-72
-36
0
36
144
108
72
MAX4475 toc17
VDD = 3V OR 5V
RL = 50k
CL = 20pF
AV = +1000V/V
GAIN
PHASE
1000 100,000
-130
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
0
0.001 0.1 10
MAX4475–MAX4478
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
MAX4475 toc18
FREQUENCY (kHz)
PSRR (dB)
VDD = 3V OR 5V
1000
100
10
1
0.1
0.01
1 100 1k10 10k
OUTPUT IMPEDANCE vs. FREQUENCY
MAX4475 toc19
FREQUENCY (Hz)
OUTPUT IMPEDANCE ()
AV = +5
AV = +1
MAX4475–MAX4478/
MAX4488/MAX4489
6
Maxim Integrated
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
25
20
10
5
0
10 1k 10k100 100k
INPUT VOLTAGE-NOISE DENSITY
vs. FREQUENCY
MAX4475 toc20
FREQUENCY (Hz)
15
VIN EQUIVALENT INPUT NOISE VOLTAGE (nV/Hz)
1s/div
0.1Hz TO 10HzP-P NOISE
VDD = 3V OR 5V
VP-P NOISE = 260nVP-P
200nV/div
MAX4475 toc21
MAX4475
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE SWING
MAX4475 toc22
OUTPUT VOLTAGE (VP-P)
THD + N (%)
10
0.0001
0.001
0.01
0.1
1
02134
fO = 20kHz, FILTER BW = 80kHz
fO = 3kHz, FILTER BW = 30kHz
AV = +1
RL = 100k
MAX4488/MAX4489
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE SWING
OUTPUT VOLTAGE (VP-P)
0213
THD + N (%)
10
0.00001
0.0001
0.001
0.01
1
0.1
MAX4475 toc23
VDD = +3V, fO = 20kHz
FILTER BW = 80kHz
VDD = 3V, fO = 3kHz
FILTER BW = 30kHz
AV = +5
RL = 100k
0.01
0.0001
0 10k 20k
MAX4488/MAX4489
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX4475 toc24
FREQUENCY (Hz)
THD + N (%)
0.001
5k 15k
FILTER BW = 22kHz
RL = 10k TO GND
R1 = 5.6k, R2 = 53k
VOUT = 2VP-P
AV = +10, VDD = 3V
AV = +10, VDD = 5V
0.01
0.001
0 20k
MAX4475–MAX4478
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX4475 toc25
FREQUENCY (Hz)
THD + N (%)
5k 10k 15k
FILTER BW = 80kHz
VOUT = 2VP-P
AV = +1
RL = 1k
RL TO VDD/2 RL TO GND
RL TO VDD
1
0.0001
0 5k 15k 20k
MAX4488/MAX4489
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
0.001
0.01
0.1
MAX4475 toc26
FREQUENCY (Hz)
THD + N (%)
10k
FILTER BW = 80kHz
RL = 10k TO GND
R1 = 2.43k, R2 = 10k
VOUT = 2.75VP-P
AV = +5, VDD = 3V
AV = +5, VDD = 5V
Typical Operating Characteristics (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, input noise floor of test equipment =10nV/Hz for all distortion
measurements, TA= +25°C, unless otherwise noted.)
1µs/div
MAX4475–MAX4478
LARGE-SIGNAL PULSE RESPONSE
VDD = 3V, RL = 10k, CL = 100pF
VIN = 2V
0.5V
MAX4475 toc27
2.5V
4µs/div
MAX4475–MAX4478
SMALL-SIGNAL PULSE RESPONSE
VDD = 3V, RL = 10k, CL = 100pF
VIN = 100mV PULSE
0.5V
MAX4475 toc28
0.6V
20mV/div
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
7
Pin Description
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Typical Operating Characteristics (continued)
(VDD = +5V, VSS = 0V, VCM = 0V, VOUT = VDD/2, RLtied to VDD/2, input noise floor of test equipment =10nV/Hz for all distortion
measurements, TA= +25°C, unless otherwise noted.)
1µs/div
MAX4488/MAX4489
LARGE-SIGNAL PULSE RESPONSE
VDD = 3V, RL = 10k, CL = 50pF
VIN = 20mV PULSE, AV = +5V/V
MAX4475 toc29
VOUT
200mV/div
1µs/div
MAX4488/MAX4489
SMALL-SIGNAL PULSE RESPONSE
VDD = 3V, RL = 10k, CL = 50pF
VIN = 20mV PULSE, AV = +5V/V
MAX4475 toc30
VOUT
50mV/div
1.6V
1.5V
-20
-90
10 1000100 100k 100M10M
MAX4477/MAX4478/MAX4489
CROSSTALK vs. FREQUENCY
-60
-50
-40
-30
MAX4475 toc31
FREQUENCY (Hz)
CROSSTALK (dB)
10k 1M
-70
-80
PIN
MAX4475/
MAX4488
MAX4475/
MAX4488 MAX4476 MAX4477/
MAX4489 MAX4478
SOT23/TDFN SO/µMAX SOT23/TDFN SO/µMAX SO/TSSOP
NAME FUNCTION
1 6 1 1, 7 1, 7, 8, 14
OUT, OUTA,
OUTB, OUTC,
OUTD
Amplifier Output
242411
VSS
Negative Supply. Connect
to ground for single-
supply operation
3 3 3 3, 5 3, 5, 10, 12
IN+, INA+,
INB+, INC+,
IND+
Noninverting Amplifier
Input
4 2 4 2, 6 2, 6, 9, 13 IN-, INA-, INB-,
INC-, IND- Inverting Amplifier Input
67684VDD Positive Supply
58
SHDN
Shutdown Input. Connect
to VDD for normal
operation (amplifier(s)
enabled).
1, 5 5 N.C. No Connection. Not
internally connected.
EP (TDFN
only) EP (TDFN
only) —— EP
Exposed Paddle. Connect
to VSS.
MAX4475–MAX4478/
MAX4488/MAX4489
8
Maxim Integrated
Detailed Description
The MAX4475–MAX4478/MAX4488/MAX4489 single-
supply operational amplifiers feature ultra-low noise
and distortion. Their low distortion and low noise make
them ideal for use as preamplifiers in wide dynamic-
range applications, such as 16-bit analog-to-digital
converters (see
Typical Operating Circuit
). Their high-
input impedance and low noise are also useful for sig-
nal conditioning of high-impedance sources, such as
piezoelectric transducers.
These devices have true rail-to-rail ouput operation,
drive loads as low as 1kwhile maintining DC accura-
cy, and can drive capactive loads up to 200pF without
oscillation. The input common-mode voltage range
extends from (VDD - 1.6V) to 200mV below the negative
rail. The push-pull output stage maintains excellent DC
characteristics, while delivering up to ±5mA of current.
The MAX4475–MAX4478 are unity-gain stable, while
the MAX4488/MAX4489 have a higher slew rate and
are stable for gains 5V/V. The MAX4475/MAX4488
feature a low-power shutdown mode, which reduces
the supply current to 0.01µA and disables the outputs.
Low Distortion
Many factors can affect the noise and distortion that the
device contributes to the input signal. The following
guidelines offer valuable information on the impact of
design choices on Total Harmonic Distortion (THD).
Choosing proper feedback and gain resistor values for
a particular application can be a very important factor
in reducing THD. In general, the smaller the closed-
loop gain, the smaller the THD generated, especially
when driving heavy resistive loads. The THD of the part
normally increases at approximately 20dB per decade,
as a function of frequency. Operating the device near
or above the full-power bandwidth significantly
degrades distortion.
Referencing the load to either supply also improves the
part’s distortion performance, because only one of the
MOSFETs of the push-pull output stage drives the out-
put. Referencing the load to midsupply increases the
part’s distortion for a given load and feedback setting.
(See the Total Harmonic Distortion vs. Frequency graph
in the
Typical Operating Characteristics
.)
For gains 5V/V, the decompensated devices
MAX4488/MAX4489 deliver the best distortion perfor-
mance, since they have a higher slew rate and provide
a higher amount of loop gain for a given closed-loop
gain setting. Capacitive loads below 100pF do not sig-
nificantly affect distortion results. Distortion perfor-
mance is relatively constant over supply voltages.
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
CZ
RF
VOUT
VIN
RG
VOUT
100mV/div
VIN
100mV/div
100mV
0V
AV = +2
RF = RG = 100k
2µs/div
Figure 1. Adding Feed-Forward Compensation
Figure 2a. Pulse Response with No Feed-Forward
Compensation
VOUT
100mV/div
VIN
100mV/div
AV = +2
RF = RG = 100k
2µs/div
Figure 2b. Pulse Response with 10pF Feed-Forward
Compensation
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
9
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Low Noise
The amplifier’s input-referred noise-voltage density is
dominated by flicker noise at lower frequencies, and by
thermal noise at higher frequencies. Because the ther-
mal noise contribution is affected by the parallel combi-
nation of the feedback resistive network (RF|| RG,
Figure 1), these resistors should be reduced in cases
where the system bandwidth is large and thermal noise
is dominant. This noise contribution factor decreases,
however, with increasing gain settings.
For example, the input noise-voltage density of the cir-
cuit with RF= 100k, RG= 11k(AV= +5V/V) is
en= 14nV/Hz, encan be reduced to 6nV/Hz by
choosing RF= 10k, RG= 1.1k(AV= +5V/V), at the
expense of greater current consumption and potentially
higher distortion. For a gain of 100V/V with RF= 100k,
RG= 1.1k, the enis still a low 6nV/Hz.
Using a Feed-Forward Compensation
Capacitor, C
Z
The amplifier’s input capacitance is 10pF. If the resis-
tance seen by the inverting input is large (feedback
network), this can introduce a pole within the amplifier’s
bandwidth resulting in reduced phase margin.
Compensate the reduced phase margin by introducing
a feed-forward capacitor (CZ) between the inverting
input and the output (Figure 1). This effectively cancels
the pole from the inverting input of the amplifier.
Choose the value of CZas follows:
CZ= 10 x (RF/ RG) [pF]
In the unity-gain stable MAX4475–MAX4478, the use of
a proper CZis most important for AV= +2V/V, and
AV = -1V/V. In the decompensated MAX4488/
MAX4489, CZis most important for AV= +10V/V.
Figures 2a and 2b show transient response both with
and without CZ.
Using a slightly smaller CZthan suggested by the for-
mula above achieves a higher bandwidth at the
expense of reduced phase and gain margin. As a gen-
eral guideline, consider using CZfor cases where RG||
RFis greater than 20k(MAX4475–MAX4478) or
greater than 5k(MAX4488/MAX4489).
Applications Information
The MAX4475–MAX4478/MAX4488/MAX4489 combine
good driving capability with ground-sensing input and
rail-to-rail output operation. With their low distortion and
low noise, they are ideal for use in ADC buffers, med-
ical instrumentation systems and other noise-sensitive
applications.
Ground-Sensing and Rail-to-Rail Outputs
The common-mode input range of these devices
extends below ground, and offers excellent common-
mode rejection. These devices are guaranteed not to
undergo phase reversal when the input is overdriven
(Figure 3).
Figure 4 showcases the true rail-to-rail output operation
of the amplifier, configured with AV= 5V/V. The output
swings to within 8mV of the supplies with a 10kload,
making the devices ideal in low-supply voltage applica-
tions.
Power Supplies and Layout
The MAX4475–MAX4478/MAX4488/MAX4489 operate
from a single +2.7V to +5.5V power supply or from dual
supplies of ±1.35V to ±2.75V. For single-supply opera-
tion, bypass the power supply with a 0.1µF ceramic
VOUT
2V/div
VIN
2V/div
0V
AV = +1
VDD = +5V
RL = 10k
40µs/div
VOUT
1V/div
5V
0V
20µs/div
Figure 3. Overdriven Input Showing No Phase Reversal
Figure 4. Rail-to-Rail Output Operation
MAX4475–MAX4478/
MAX4488/MAX4489
10
Maxim Integrated
capacitor placed close to the VDD pin. If operating from
dual supplies, bypass each supply to ground.
Good layout improves performance by decreasing the
amount of stray capacitance and noise at the op amp’s
inputs and output. To decrease stray capacitance, min-
imize PC board trace lengths and resistor leads, and
place external components close to the op amp’s pins.
Typical Application Circuit
The
Typical Application Circuit
shows the single
MAX4475 configured as an output buffer for the
MAX5541 16-bit DAC. Because the MAX5541 has an
unbuffered voltage output, the input bias current of the
op amp used must be less than 6nA to maintain 16-bit
accuracy. The MAX4475 has an input bias current of
only 150pA (max), virtually eliminating this as a source
of error. In addition, the MAX4475 has excellent open-
loop gain and common-mode rejection, making this an
excellent ouput buffer amplifier.
DC-Accurate Lowpass Filter
The MAX4475–MAX4478/MAX4488/MAX4489 offer a
unique combination of low noise, wide bandwidth, and
high gain, making them an excellent choice for active
filters up to 1MHz. The
Typical Operating Circuit
shows
the dual MAX4477 configured as a 5th order
Chebyschev filter with a cutoff frequency of 100kHz.
The circuit is implemented in the Sallen-Key topology,
making this a DC-accurate filter.
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Typical Application Circuit
0 to +2.5V
OUTPUT
SHDN
8
4
CS
SCLK
DIN
2
3
SERIAL
INTERFACE
VDD
DGND
REF
OUT
AGND
+5V +2.5V +5V
7
6
U1
MAX5541ESA
U2
MAX
4475AUA
Typical Operating Circuit
1
2
3
4
5
6
7
8
470pF
3.09k
1%
3.83k
1%
13.7k
1%
7.87k
1%
10.0k
1%
10.0k
1%
15.0k
1%
7.15k
1%
10.0k
1%
0.1µF
220pF
220pF
220pF
220pF
5V
MAX4477
1/2
MAX4477
1/2
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
11
Pin Configurations
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
OUT
N.C.VSS
1
2
8
7VDD
INA-
INA+
N.C.
SO/µMAX
TOP VIEW
3
4
6
5
MAX4475
MAX4488
SHDN
INB-
OUTB
INB+VSS
1
2
8
7
VDD
INA-
INA+
OUTA
SO/µMAX
TOP VIEW
3
4
6
5
MAX4477
MAX4489
14
13
12
11
10
9
8
1
2
3
4
5
6
7
OUTD
IND-
IND+
VSS
VDD
INA+
INA-
OUTA
TOP VIEW
MAX4478
INC+
INC-
OUTCOUTB
INB-
INB+
SO/TSSOP
VSS
IN-IN+
16VDD
5
OUT
MAX4475
MAX4488
SOT23-6
TOP VIEW
2
34
SHDN
N.C.
VSS
IN-IN+
16VDD
OUT
MAX4476
SOT23-6
TOP VIEW
2
34
5
MAX4475
MAX4488
TOP VIEW
6
VDD
5
SHDN
4
IN-
OUT
VSS
IN+
123
TDFN
*EP = EXPOSED PADDLE.
*EP
+
MAX4476
TOP VIEW
6
VDD
5
N.C.
4
IN-
OUT
VSS
IN+
123
TDFN
*EP = EXPOSED PADDLE.
*EP
+
MAX4475–MAX4478/
MAX4488/MAX4489
12
Maxim Integrated
Ordering Information (continued)
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Chip Information
PROCESS: BiCMOS
PART TEMP RANGE PIN-
PACKAGE
TOP
MARK
MAX4476AUT+T -40°C to +125°C 6 SOT23 AAZX
MAX4476ATT+T -40°C to +125°C 6 TDFN-EP* +ADF
MAX4477AUA+ -40°C to +125°C 8 µMAX
MAX4477AUA+ -40°C to +125°C 8 µMAX
MAX4477ASA+ -40°C to +125°C 8 SO
MAX4478AUD+ -40°C to +125°C 14 TSSOP
MAX4478AUD/V+ -40°C to +125°C 14 TSSOP
MAX4478ASD+ -40°C to +125°C 14 SO
MAX4488AUT+T -40°C to +125°C 6 SOT23 AAZW
MAX4488AUA+ -40°C to +125°C 8 µMAX
MAX4488ASA+ -40°C to +125°C 8 SO
MAX4488ATT+T -40°C to +125°C 6 TDFN-EP* +ADE
MAX4489AUA+ -40°C to +125°C 8 µMAX
+
Denotes a lead(Pb)-free/RoHS-compliant package.
*
EP = Exposed pad (connect to VSS).
/V denotes an automotive qualified part.
T = Tape and reel.
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
13
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND
PATTERN NO.
6 SOT23 U6F-6 21-0058 90-0175
8 µMAX U8-1 21-0036 90-0092
14 TSSOP U14-2 21-0066 90-0117
8 SO S8-4 21-0041
14 SO S14-4 21-0041
6 TDFN-EP T633-2 21-0137 90-0058
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.
MAX4475–MAX4478/
MAX4488/MAX4489
14
Maxim Integrated
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
15
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.
α
α
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
MAX4475–MAX4478/
MAX4488/MAX4489
16
Maxim Integrated
SOT23, Low-Noise, Low-Distortion,
Wide-Band, Rail-to-Rail Op Amps
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the
package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the
package regardless of RoHS status.
MAX4475–MAX4478/
MAX4488/MAX4489
Maxim Integrated
17