General Description
The MAX4249–MAX4257 low-noise, low-distortion oper-
ational amplifiers offer rail-to-rail outputs and single-
supply operation down to 2.4V. They draw 400µA of
quiescent supply current per amplifier while featuring
ultra-low distortion (0.0002% THD), as well as low input
voltage-noise density (7.9nV/Hz) and low input
current-noise density (0.5fA/Hz). These features make
the devices an ideal choice for portable/battery-powered
applications that require low distortion and/or low noise.
For additional power conservation, the MAX4249/
MAX4251/MAX4253/MAX4256 offer a low-power shut-
down mode that reduces supply current to 0.5µA and
puts the amplifiers’ outputs into a high-impedance
state. The MAX4249-MAX4257’s outputs swing rail-to-
rail and their input common-mode voltage range
includes ground. The MAX4250–MAX4254 are unity-
gain stable with a gain-bandwidth product of 3MHz.
The MAX4249/MAX4255/MAX4256/MAX4257 are inter-
nally compensated for gains of 10V/V or greater with a
gain-bandwidth product of 22MHz. The single MAX4250/
MAX4255 are available in space-saving 5-pin SOT23
packages. The MAX4252 is available in an 8-bump chip-
scale package (UCSP™) and the MAX4253 is available in
a 10-bump UCSP. The MAX4250AAUK comes in a 5-pin
SOT23 package and is specified for operation over the
automotive (-40°C to +125°C) temperature range.
Applications
Wireless Communications Devices
PA Control
Portable/Battery-Powered Equipment
Medical Instrumentation
ADC Buffers
Digital Scales/Strain Gauges
Features
Available in Space-Saving UCSP, SOT23, and
µMAX®Packages
Low Distortion: 0.0002% THD (1kΩload)
400µA Quiescent Supply Current per Amplifier
Single-Supply Operation from 2.4V to 5.5V
Input Common-Mode Voltage Range Includes
Ground
Outputs Swing Within 8mV of Rails with a 10kΩ
Load
3MHz GBW Product, Unity-Gain Stable
(MAX4250–MAX4254)
22MHz GBW Product, Stable with AV10V/V
(MAX4249/MAX4255/MAX4256/MAX4257)
Excellent DC Characteristics
VOS = 70µV
IBIAS = 1pA
Large-Signal Voltage Gain = 116dB
Low-Power Shutdown Mode
Reduces Supply Current to 0.5µA
Places Outputs in a High-Impedance State
400pF Capacitive-Load Handling Capability
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
________________________________________________________________ Maxim Integrated Products 1
19-1295; Rev 7; 4/05
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information continued at end of data sheet.
Selector Guide appears at end of data sheet.
UCSP is a trademark and µMAX is a registered trademark of Maxim Integrated Products, Inc.
A
B
C
12 3
OUTA VDD OUTB
INA- INB-
INB+
VSS
INA+
MAX4252
OUTA
VDD
OUTB
INA-
INB-
INA+
INB+
VSS
SHDNA
SHDNB
MAX4253
C1
B1
A1 A2 A3 A4
B4
C2 C3 C4
TOP VIEW
(BUMPS ON BOTTOM)
UCSP
UCSP
Pin Configurations continued at end of data sheet.
Pin Configurations
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
TOP
MARK
MAX4249ESD
-40°C to +85°C
14 SO
MAX4249EUB
-40°C to +85°C
10 µMAX
MAX4250EUK-T
-40°C to +85°C
5 SOT23-5
ACCI
M AX 4250AAU K- T
- 40°C to + 125°C
5 SOT23-5
AEYJ
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD = 5V, VSS = 0, VCM = 0, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= TMIN to TMAX, unless otherwise noted. Typical val-
ues are at TA= +25°C.) (Notes 2, 3)
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) ......................+6.0V to -0.3V
Analog Input Voltage (IN_+, IN_-)....(VDD + 0.3V) to (VSS - 0.3V)
SHDN Input Voltage ......................................6.0V to (VSS - 0.3V)
Output Short-Circuit Duration to Either Supply ..........Continuous
Continuous Power Dissipation (TA= +70°C)
5-Pin SOT23 (derate 7.1mW/°C above +70°C)...........571mW
8-Bump UCSP (derate 4.7mW/°C above +70°C)........379mW
8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW
8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW
10-Bump UCSP (derate 6.1mW/°C above +70°C) ......484mW
10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW
14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW
Operating Temperature Range ...........................-40°C to +85°C
MAX4250AAUK .............................................-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Bump Temperature (soldering) (Note 1)
Infrared (15s) ................................................................+220°C
Vapor Phase (60s) ........................................................+215°C
PARAMETER
SYMBOL
CONDITIONS MIN TYP
UNITS
Supply Voltage Range VDD (Note 4) 2.4 5.5 V
VDD = 3V 400
E temperature 420 575
VDD = 5V
MAX4250AAUK 675
Normal
mode
VDD = 5V, UCSP only 420 655
Quiescent Supply Current Per
Amplifier IQ
Shutdown mode (SHDN = VSS) (Note 2) 0.5 1.5
µA
E temperature
±0.07 ±0.75
Input Offset Voltage (Note 5) VOS MAX4250AAUK
±1.85
mV
Input Offset Voltage Tempco
TCVOS
0.3
µV/°C
E temperature ±1
±100
pA
Input Bias Current IB(Note 6) MAX4250AAUK
±10
nA
E temperature ±1
±100
pA
Input Offset Current IOS (Note 6) MAX4250AAUK
±10
nA
Differential Input Resistance RIN
1000
G
E temperature -0.2
VDD -1.1
Input Common-Mode Voltage
Range VCM Guaranteed by
CMRR test MAX4250AAUK 0
VDD -1.1
V
E temperature 70 115
Common-Mode Rejection Ratio
CMRR
VSS - 0.2V VCM
VDD - 1.1V MAX4250AAUK 68 dB
E temperature 75 100
Power-Supply Rejection Ratio
PSRR
VDD = 2.4V to 5.5V MAX4250AAUK 72 dB
Note 1: This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device
can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles rec-
ommended in the industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and Convection
Reflow. Preheating is required. Hand or wave soldering is not allowed.
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 5V, VSS = 0, VCM = 0, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= TMIN to TMAX, unless otherwise noted. Typical val-
ues are at TA= +25°C.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS MIN TYP
MAX
UNITS
E temperature 80 116
RL = 10k to VDD/2;
VOUT = 25mV to VDD
- 4.97V MAX4250AAUK 77
E temperature 80 112
Large-Signal Voltage Gain AVRL = 1k to VDD/2;
VOUT = 150V to VDD -
4.75V MAX4250AAUK 77
dB
E825
VDD - VOH
A30
E720
Output Voltage Swing VOUT |VIN+ - VIN-| 10mV;
RL = 10k to VDD/2
VOL - VSS
A25
mV
E 77 200
VDD - VOH
A 225
E 47 100
Output Voltage Swing VOUT |VIN+ - VIN-| 10mV,
RL = 1k to VDD/2
VOL - VSS
A 125
mV
Output Short-Circuit Current ISC 68 mA
Output Leakage Current ILEAK Shutdown mode (SHDN = VSS),
VOUT = VSS to VDD (Note 2)
0.001
1.0 µA
SHDN Logic Low VIL (Note 2)
0.2 X V
D D
V
SHDN Logic High VIH (Note 2)
0.8 X VDD
V
SHDN Input Current IIL/IIH SHDN = VSS = VDD (Note 2) 0.5 1.5 µA
Input Capacitance 11 pF
MAX4250–MAX4254 3
Gain-Bandwidth Product GBW
MAX4249/MAX4255/MAX4256/MAX4257 22
MHz
MAX4250–MAX4254 0.3
Slew Rate SR
MAX4249/MAX4255/MAX4256/MAX4257 2.1
V/µs
Peak-to-Peak Input-Noise
Voltage enP-P f = 0.1Hz to 10Hz 760
nVP-P
f = 10Hz 27
f = 1kHz 8.9
Input Voltage-Noise Density en
f = 30kHz 7.9
nV/Hz
Input Current-Noise Density inf = 1kHz 0.5
fA/Hz
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 5V, VSS = 0, VCM = 0, VOUT = VDD/2, RLtied to VDD/2, SHDN = VDD, TA= TMIN to TMAX, unless otherwise noted. Typical val-
ues are at TA= +25°C.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS MIN TYP
UNITS
f = 1kHz
0.0004
MAX4250–MAX4254
AV = 1V/V, VOUT = 2VP-P,
RL = 1k to GND
(Note 7) f = 20kHz
0.006
f = 1kHz
0.0012
Total Harmonic Distortion Plus
Noise
THD+N
MAX4249/MAX4255/
MAX4256/MAX4257
AV = 1V/V, VOUT = 2VP-P,
RL = 1k to GND (Note 7)
f = 20kHz
0.007
%
Capacitive-Load Stability No sustained oscillations 400 pF
MAX4250–MAX4254, AV = 1V/V 10
Gain Margin GM MAX4249/MAX4255/MAX4256/MAX4257,
AV = 10V/V 12.5
dB
MAX4250–MAX4254, AV = 1V/V 74
Phase Margin ΦMMAX4249/MAX4255/MAX4256/MAX4257,
AV = 10V/V 68
Degrees
MAX4250–MAX4254 6.7
Settling Time To 0.01%, VOUT
= 2V step MAX4249/MAX4255/
MAX4256/MAX4257 1.6 µs
MAX4251/MAX4253 0.8
Delay Time to Shutdown tSH
IVDD = 5% of
normal
operation MAX4249/MAX4256 1.2
µs
MAX4251/MAX4253 8
Delay Time to Enable tEN
VOUT = 2.5V,
VOUT settles to
0.1% MAX4249/MAX4256 3.5
µs
Power-Up Delay Time tPU VDD = 0 to 5V step, VOUT stable to 0.1% s
Note 2: SHDN is available on the MAX4249/MAX4251/MAX4253/MAX4256 only.
Note 3: All device specifications are 100% tested at TA= +25°C. Limits over temperature are guaranteed by design.
Note 4: Guaranteed by the PSRR test.
Note 5: Offset voltage prior to reflow on the UCSP.
Note 6: Guaranteed by design.
Note 7: Lowpass-filter bandwidth is 22kHz for f = 1kHz and 80kHz for f = 20kHz. Noise floor of test equipment = 10nV/Hz.
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
_______________________________________________________________________________________ 5
0
10
5
20
15
25
30
35
40
-95
-55
-35
-75
-13
7
28
49
69
90
110
131
152
172
192
MAX4251/MAX4256
INPUT OFFSET VOLTAGE DISTRIBUTION
MAX4249-57 TOC01
VOS (μV)
NUMBER OF UNITS
400 UNITS
VCM = 0
TA = +25°C
-250
-100
-150
-200
-50
0
50
100
150
200
250
-40 0-20 20 40 60 80
OFFSET VOLTAGE
vs. TEMPERATURE
MAX4249-57 TOC02
TEMPERATURE (°C)
VCM = 0
VOS (μV)
-50
0
100
50
150
200
-0.5 1.50.5 2.5 3.5 4.5
MAX4249-57 TOC03
INPUT COMMON-MODE VOLTAGE (V)
INPUT OFFSET VOLTAGE (μV)
VDD = 3V VDD = 5V
INPUT OFFSET VOLTAGE
vs. INPUT COMMON-MODE VOLTAGE
0
0.3
0.2
0.1
0.4
0.5
0.6
04312 5678910
OUTPUT VOLTAGE
vs. OUTPUT LOAD CURRENT
MAX4249-57 TOC04
OUTPUT LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
VDD = 3V OR 5V
VDIFF = ±10mV
VDD - VOH
VOL
0
0.03
0.02
0.01
0.04
0.05
0.06
0.07
0.08
0.09
0.10
-40 0-20 20 6040 80
OUTPUT VOLTAGE SWING (VOH)
vs. TEMPERATURE
MAX4249-57 TOC05
TEMPERATURE (°C)
RL = 1kΩ
RL = 10kΩ
RL = 100kΩ
VDD - VOH (V)
0
0.02
0.01
0.03
0.04
0.05
0.06
-40 0-20 20 6040 80
OUTPUT VOLTAGE SWING (VOL)
vs. TEMPERATURE
MAX4249 -57TOC06
TEMPERATURE (°C)
VOL (V)
RL = 10kΩ
RL = 1kΩ
RL = 100kΩ
50
70
60
100
90
80
130
120
110
140
0 10050 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4249-57 TOC07
VOUT SWING FROM EITHER SUPPLY (mV)
VDD = 3V
RL REFERENCED TO GND
RL = 2kΩ
RL = 20kΩ
RL = 200kΩ
AV (dB)
60
70
80
90
100
110
120
130
140
0 50 100 150 200 250
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
MAX4249-57 TOC08
VOUT SWING FROM EITHER SUPPLY (mV)
VDD = 3V
RL REFERENCED TO GND
RL = 2kΩ
RL = 20kΩRL = 200kΩ
AV (dB)
50
70
60
100
90
80
130
120
110
140
0 10050 150 200 250
MAX4249-57 TOC09
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
VOUT SWING FROM EITHER SUPPLY (mV)
VDD = 5V
RL REFERENCED TO GND
RL = 2kΩ
RL = 20kΩ
RL = 200kΩ
AV (dB)
Typical Operating Characteristics
(VDD = 5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/Hz for all distortion measurements,
TA= +25°C, unless otherwise noted.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
6 _______________________________________________________________________________________
50
80
70
60
90
100
110
120
130
140
150
0 10050 150 200 250
MAX4249-57 TOC10
VDD = 5V
RL REFERENCED TO GND
LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING
VOUT SWING FROM EITHER SUPPLY (mV)
RL = 2kΩ
RL = 20kΩ
RL = 200kΩ
AV (dB)
100
110
105
115
120
125
-40 0-20 20 6040 80
LARGE-SIGNAL VOLTAGE GAIN
vs. TEMPERATURE
MAX4249-57 TOC11
TEMPERATURE (°C)
RL REFERENCED TO VDD/2
VDD = 5V
AV (dB)
RL = 1kΩ
VOUT = 150mV
TO 4.75mV
RL = 100kΩ
VOUT = 10mV
TO 4.99mV
RL = 10kΩ
VOUT = 20mV
TO 4.975mV
0.373
0.374
0.375
0.376
340
380
360
400
420
440
460
-40 0-20 20 6040 80
SUPPLY CURRENT AND SHUTDOWN
SUPPLY CURRENT vs. TEMPERATURE
MAX4249-57 TOC12
TEMPERATURE (°C)
SHUTDOWN SUPPLY CURRENT (μA)
PER AMPLIFIER
SHDN = VDD
SUPPLY CURRENT (μA)
SHDN = VSS
320
340
360
380
400
420
440
0
0.1
0.2
0.3
0.4
0.5
0.6
1.8 2.82.3 3.3 3.8 4.3 4.8 5.3 5.5
SUPPLY CURRENT AND SHUTDOWN
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX4249-57 TOC13
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (μA)
SHUTDOWN SUPPLY CURRENT (μA)
PER AMPLIFIER
SHDN = VDD
SHDN = VSS
2000
100
0.001 0.1 10.01 5
SUPPLY CURRENT
vs. OUTPUT VOLTAGE
MAX4249-57 TOC14
OUTPUT VOLTAGE (V)
SUPPLY CURRENT (μA)
1000
400
VDD = 5V
VDD = 3V
40
60
80
120
100
180
160
140
1.8 2.3 2.8 3.3 3.8 4.3 4.8 5.3
INPUT OFFSET VOLTAGE
vs. SUPPLY VOLTAGE
MAX4249-57 TOC15
SUPPLY VOLTAGE (V)
VOS (μV)
VCM = 0
VOUT = VDD/2
RL REFERENCED TO GND
RL = 10kΩ
RL = 1kΩ
RL = 100kΩ
60
-40
100 10k 100k 1M1k 10M
MAX4250–MAX4254
GAIN AND PHASE vs. FREQUENCY
-20
-10
0
-30
MAX4249-57 TOC16
FREQUENCY (Hz)
GAIN (dB)
PHASE (DEGREES)
10
20
30
40
50
180
-180
-108
-72
-36
-144
0
36
72
108
144
GAIN
PHASE
VDD = 3V, 5V
RL = 50kΩ
CL = 20pF
AV = 1000
60
-40
100 10k 100k 1M1k 10M
MAX4249/MAX4255/MAX4256/MAX4257
GAIN AND PHASE vs. FREQUENCY
-20
-10
0
-30
MAX4249-57 TOC17
FREQUENCY (Hz)
GAIN (dB)
PHASE (DEGREES)
10
20
30
40
50
180
-180
-108
-72
-36
-144
0
36
72
108
144
GAIN
PHASE
VDD = 3V, 5V
RL = 50kΩ
CL = 20pF
AV = 1000
0
-100
-110
1 1k 10k 100k 1M10 100 10M
MAX4250–MAX4254
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
-80
-70
-60
-90
MAX4249-57 TOC18
FREQUENCY (Hz)
PSRR (dB)
-50
-40
-30
-20
-10
PSRR+
PSRR-
VDD = 3V, 5V
Typical Operating Characteristics (continued)
(VDD = 5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/Hz for all distortion measurements,
TA= +25°C, unless otherwise noted.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
_______________________________________________________________________________________ 7
1000
0.1
1k 10k 100k 1M 10M
OUTPUT IMPEDANCE
vs. FREQUENCY
MAX4249-57 TOC19
FREQUENCY (Hz)
OUTPUT IMPEDANCE (Ω)
1
10
100
AV = 1 (MAX4250–MAX4254)
AV = 10 (MAX4249/MAX4255/
MAX4256/MAX4257)
30
0
10 100 1k 10k 100k
INPUT VOLTAGE-N0ISE DENSITY
vs. FREQUENCY
MAX4249-57 TOC20
FREQUENCY (Hz)
Vn-EQUIVALENT INPUT NOISE-VOLTAGE (nV/Hz)
5
10
15
20
25
200nV/div
1s/div
0.1Hz TO 10HzP-P NOISE
MAX4249-57 TOC21
VDD = 3V OR 5V
VP-PNOISE = 760nVP-P
-160
-140
-120
-100
-80
-60
-40
-20
0
MAX4250–MAX4254
FFT OF DISTORTION AND NOISE
FREQUENCY (Hz)
AMPLITUDE (dBc)
10 5k 10k 15k 20k
MAX4249-57 TOC22
RL = 1kΩ
fO = 1kHz
AV = 1
fO
HD2
HD3
HD4
HD5
VOUT = 2VP-P
-140
-120
-100
-80
-60
-40
-20
0
20
10 5k 10k 15k 20k
MAX4249/MAX4255/MAX4256/MAX4257
FFT OF DISTORTION AND NOISE
MAX4249-57 TOC23
FREQUENCY (Hz)
AMPLITUDE (dBc)
VOUT = 4VP-P
fO = 1kHz
HD2
HD3
VIN
10kΩ
100kΩ
11kΩ
fO
VO
0.001
0.01
0.1
1
10
021 345
MAX4250–MAX4254
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE (VDD = 5V)
MAX4249-57 TOC24
OUTPUT VOLTAGE (VP-P)
THD+N (%)
VIN
RL = 1kΩ
100kΩ
11kΩ
AV = 10
fO = 3kHz
FILTER BW = 30kHz VO
RL
RL = 10kΩ
RL = 100kΩ
0.001
0.01
0.1
1
10
0213
MAX4249-57 TOC25
OUTPUT VOLTAGE (VP-P)
THD+N (%)
100kΩ
11kΩ
MAX4250–MAX4254
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE SWING (VDD = 3V)
VOUT
VIN
RL
RL = 1kΩ
RL = 10kΩ
RL = 100kΩ
AV = 10
fO = 3kHz
FILTER BW = 30kHz
0.001
0.01
0.1
1
03412 5
MAX4249-57 TOC26
OUTPUT VOLTAGE (VP-P)
THD+N (%)
fO = 20kHz, FILTER BW = 80kHz
100kΩ
11kΩ
MAX4249/MAX4255/MAX4256/MAX4257
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE SWING
VOUT
VIN
RL
AV = 10
fO = 3kHz, FILTER BW = 30kHz
0.0001
0.01
0.001
0.1
1
10 1k100 10k
MAX4250–MAX4254
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX4249-57 TOC27
FREQUENCY (Hz)
THD+N (%)
R2
R1
R1 = 560Ω, R2 = 53kΩ
VIN
VOUT
RL
AV = 100
AV = 10
R1 = 5.6kΩ, R2 = 53kΩ
FILTER BW = 22kHz
RL = 10kΩ TO GND
VO = 2VP-P
AV = 1
Typical Operating Characteristics (continued)
(VDD = 5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/Hz for all distortion measurements,
TA= +25°C, unless otherwise noted.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
8 _______________________________________________________________________________________
0.0001
0.001
0.01
0.1
10 1k100 10k
MAX4250–MAX4254
TOTAL HARMONIC DISTORTION
PLUS NOISE vs. FREQUENCY
MAX4249-57 TOC28
FREQUENCY (Hz)
THD+N(%)
FILTER BW = 80kHz
AV = 1
RL = 1kΩ
VOUT = 2VP-P
RL TO VDD/2
RL TO GND
RL TO VDD
VOUT
200mV/div
1.5V
0.5V
2μs/div
MAX4250–MAX4254
LARGE-SIGNAL PULSE RESPONSE
MAX4249-57 TOC29
VDD = 3V
RL = 10kΩ
CL = 100pF
VIN = 1V PULSE
0.6V
0.5V
MAX4249-57 TOC30
MAX4250–MAX4254
SMALL-SIGNAL PULSE RESPONSE
VOUT
20mV/div
VDD = 3V
RL = 10kΩ
CL = 100pF
VIN = 100V PULSE
2μs/div
2V
1V
MAX4249/MAX4255/MAX4256/MAX4257
LARGE-SIGNAL PULSE RESPONSE
MAX4249-57 TOC31
VOUT
200mV/div
VDD = 3V
RL = 10kΩ
CL = 100pF
VIN = 100mV PULSE
AV = 10
2μs/div
1.6V
1.5V
MAX4249/MAX4255/MAX4256/MAX4257
SMALL-SIGNAL PULSE RESPONSE
MAX4249-57 TOC32
VOUT
50mV/div
VDD = 3V
RL = 10kΩ
CL = 100pF
VIN = 10mV PULSE
AV = 10
2μs/div
140
130
0
CHANNEL SEPARATION vs. FREQUENCY
MAX4249-57 TOC33
FREQUENCY (Hz)
CHANNEL SEPARATION (dB)
100
110
120
90
80
70
1k 100k 1M10k 10M
Typical Operating Characteristics (continued)
(VDD = 5V, VSS = 0, VCM = VOUT = VDD/2, input noise floor of test equipment =10nV/Hz for all distortion measurements,
TA= +25°C, unless otherwise noted.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
_______________________________________________________________________________________ 9
Detailed Description
The MAX4249–MAX4257 single-supply operational
amplifiers feature ultra-low noise and distortion while
consuming very little power. 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
signal conditioning of high-impedance sources, such
as piezoelectric transducers.
These devices have true rail-to-rail output operation,
drive loads as low as 1kΩwhile maintaining DC accura-
cy, and can drive capacitive loads up to 400pF without
oscillation. The input common-mode voltage range
extends from VDD - 1.1V to 200mV beyond the negative
rail. The push-pull output stage maintains excellent DC
characteristics, while delivering up to ±5mA of current.
The MAX4250–4254 are unity-gain stable, whereas, the
MAX4249/MAX4255/MAX4256/MAX4257 have a higher
slew rate and are stable for gains 10V/V. The
MAX4249/MAX4251/MAX4253/MAX4256 feature a low-
power shutdown mode, which reduces the supply cur-
rent to 0.5µA and disables the outputs.
The MAX4250AAUK is specified for operation over the
automotive (-40°C to +125°C) temperature range.
Pin Description
PIN/BUMP
M A X4 2 5 0 /
M A X4 2 5 5
M A X4 2 5 1 /
M A X4 2 5 6
M A X4 2 5 2 /
M A X4 2 5 7 M A X4 2 5 2
M A X4 2 4 9 /
M A X4 2 5 3
M A X4 2 5 4
5-PIN
SOT23
8-PIN
SO/µMAX
8-PIN
SO/µMAX
8-BUMP
UCSP
10-BUMP
UCSP
10-PIN
µMAX
1 4 - PIN
SO
14-PIN
SO
NAME FUNCTION
1 6 1, 7 A1, A3
A1, C1
1, 9
1, 13
1, 7, 8,
14
OUT, OUTA,
OUTB,
OUTC,
OUTD
Amplifier Output
244C2B44411
VSS
Negative Supply.
Connect to
ground for single-
supply operation
3 3 3, 5
C1, C3 A3, C3
3, 7
3, 11
3, 5, 10,
12
IN + , IN A+ ,
IN B+ , IN C + ,
IN D +
Noninverting
Amplifier Input
4 2 2, 6 B1, B3
A2, C2
2, 8
2, 12
2, 6, 9,
13
IN-, INA-,
INB-,
INC-, IND-
Inverting
Amplifier Input
578A2B110144
VDD Positive Supply
—8
A4, C4
5, 6 6, 9
SHDN,
SHDNA,
SHDNB
Shutdown Input,
Connect to VDD
or leave
unconnected for
normal operation
(amplifier(s)
enabled).
1, 5 5, 7,
8, 10
—N.C.
No Connection.
Not internally
connected.
——B2
B2, B3
——
Not populated
with solder
sphere
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
10 ______________________________________________________________________________________
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. Large-value feed-
back resistors can significantly improve distortion. 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 10V/V, the decompensated devices
MAX4249/MAX4255/MAX4256/MAX4257 deliver the
best distortion performance, 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 400pF, do not significantly affect distortion
results. Distortion performance remains relatively con-
stant over supply voltages.
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= 100kΩ, RG= 11kΩ(AV= 10V/V) is en=
15nV/Hz, encan be reduced to 9nV/Hz by choosing
RF= 10kΩ, RG= 1.1kΩ(AV= 10V/V), at the expense
of greater current consumption and potentially higher
distortion. For a gain of 100V/V with RF= 100kΩ, RG=
1.1kΩ, the enis low (9nV/Hz).
CZ
RF
VOUT
VIN
RG
0
100mV
AV = 2V/V
RF = RG = 10kΩ
VIN =
50mV/div
VOUT =
100mV/div
2μs/div
0
100mV
AV = 2
RF = RG = 100kΩ
CZ = 11pF
50mV/div
100mV/div
VIN
VOUT
2μs/div
Figure 1. Adding Feed-Forward Compensation
Figure 2a. Pulse Response with No Feed-Forward
Compensation
Figure 2b. Pulse Response with 10pF Feed-Forward
Compensation
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
______________________________________________________________________________________ 11
Using a Feed-Forward Compensation
Capacitor, CZ
The amplifier’s input capacitance is 11pF. 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= 11 x (RF/ RG) [pF]
In the unity-gain stable MAX4250–MAX4254, the use of
a proper CZis most important for AV= 2V/V, and
AV = -1V/V. In the decompensated MAX4249/
MAX4255/MAX4256/MAX4257, 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 20kΩ(MAX4250–MAX4254) or
greater than 5kΩ(MAX4249/MAX4255/MAX4256/
MAX4257).
Applications Information
The MAX4249–MAX4257 combine good driving capa-
bility with ground-sensing input and rail-to-rail output
operation. With their low distortion, low noise, and low-
power consumption, these devices are ideal for use in
portable instrumentation systems and other low-power,
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= 10V/V. The output
swings to within 8mV of the supplies with a 10kΩload,
making the devices ideal in low-supply-voltage applica-
tions.
Output Loading and Stability
Even with their low quiescent current of 400µA, these
amplifiers can drive 1kΩloads while maintaining excel-
lent DC accuracy. Stability while driving heavy capaci-
tive loads is another key feature.
VOUT
VIN
RISO
CL
MAX4250
MAX4251
MAX4252
MAX4253
MAX4254
4.25V
4.45V
-200mV
0
0
VOUT
VIN
AV = 1
VDD = 5V
RL = 10kΩ
20μs/div
0
5V
VDD = 5V
RL = 10kΩ
AV = 10
f = 1kHz
200μs/div
VOUT
1V/div
Figure 3. Overdriven Input Showing No Phase Reversal
Figure 4. Rail-to-Rail Output Operation
Figure 5. Capacitive-Load Driving Circuit
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
12 ______________________________________________________________________________________
These devices maintain stability while driving loads up
to 400pF. To drive higher capacitive loads, place a
small isolation resistor in series between the output of
the amplifier and the capacitive load (Figure 5). This
resistor improves the amplifier’s phase margin by isolat-
ing the capacitor from the op amp’s output. Reference
Figure 6 to select a resistance value that will ensure a
load capacitance that limits peaking to <2dB (25%).
For example, if the capacitive load is 1000pF, the corre-
sponding isolation resistor is 150Ω. Figure 7 shows that
peaking occurs without the isolation resistor. Figure 8
shows the unity-gain bandwidth vs. capacitive load for
the MAX4250–MAX4254.
Power Supplies and Layout
The MAX4249–MAX4257 operate from a single 2.4V to
5.5V power supply or from dual supplies of ±1.20V to
±2.75V. For single-supply operation, bypass the power
supply with a 0.1µF ceramic 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.
UCSP Applications Information
For the latest application details on UCSP construction,
dimensions, tape carrier information, PC board tech-
niques, bump-pad layout, and recommended reflow
temperature profile, as well as the latest information on
reliability testing results, refer to the Application Note:
UCSP—A Wafer-Level Chip-Scale Package on Maxim’s
web site at www.maxim-ic.com/ucsp.
160
140
0
10 10,000
60
20
40
120
100
80
CAPACITIVE LOADING (pF)
1000100
SHADED AREA INDICATES
STABLE OPERATION
WITH NO NEED FOR
ISOLATION RESISTOR.
NOTE: USING AN ISOLATION RESISTOR REDUCES PEAKING.
RISO (Ω)
4.5
3.5
4.0
0
10 10,000
2.0
3.0
2.5
1.0
0.5
1.5
CAPACITIVE LOAD (pF)
UNITY-GAIN BANDWIDTH (MHz)
1000100
VDD = 3V
SHADED AREA INDICATES
STABLE OPERATION
WITH NO NEED FOR
ISOLATION RESISTOR.
NOTE: RISO CHOSEN FOR PEAKING <2dB.
25
20
0
10 10,000
15
5
10
CAPACITIVE LOAD (pF)
PEAKING (dB)
1000100
MAX4250–MAX4254 (AV = 1)
MAX4249/MAX4255–MAX4257 (AV = 10)
RISO = 0
SHADED AREA INDICATES
STABLE OPERATION
WITH NO NEED FOR
ISOLATION RESISTOR.
Figure 6. Isolation Resistance vs. Capacitive Loading to
Minimize Peaking (<2dB)
Figure 7. Peaking vs. Capacitive Load
Figure 8. MAX4250–MAX4254 Unity-Gain Bandwidth vs.
Capacitive Load
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
______________________________________________________________________________________ 13
Typical Operating Circuit
MAX195
(16-BIT ADC)
SERIAL
INTERFACE
DOUT
SCLK
SHDN
SHDN
AIN
VIN
REF
-5V
2
50kΩ
5V
3
4
6
7
8
5kΩ
VDD
VSS
4.096V
CS
MAX4256
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
14 ______________________________________________________________________________________
Selector Guide
PART
G A IN
B A N D WID T H
( M H z)
MINIMUM
STABLE
GAIN (V/V)
NO. OF
AMPLIFIERS
PER PACKAGE
SHUTDOWN
MODE PIN-PACKAGE
MAX4249 22 10 2 Yes 10-pin µMAX, 14-pin SO
MAX4250/A 3 1 1 5-pin SOT23
MAX4251 3 1 1 Yes 8-pin µMAX/SO
MAX4252 3 1 2
8- p i n µM AX /S O , 8- b um p U C S P
MAX4253 3 1 2 Yes 10-pin µMAX, 14-pin SO,
10-bump UCSP
MAX4254 3 1 4 14-pin SO
MAX4255 22 10 1 5-pin SOT23
MAX4256 22 10 1 Yes 8-pin µMAX/SO
MAX4257 22 10 2 8-pin µMAX/SO
PART TEMP RANGE PIN-
PACKAGE
TOP
MARK
MAX4251ESA -40°C to +85°C 8 SO
MAX4251EUA -40°C to +85°C 8 µMAX
MAX4252EBL-T -40°C to +85°C 8 UCSP-8 AAO
MAX4252ESA -40°C to +85°C 8 SO
MAX4252EUA -40°C to +85°C 8 µMAX
MAX4253EBC-T -40°C to +85°C 10 UCSP-10 AAK
MAX4253EUB -40°C to +85°C 10 µMAX
MAX4253ESD -40°C to +85°C 14 SO
MAX4254ESD -40°C to +85°C 14 SO
MAX4255EUK-T -40°C to +85°C 5 SOT23-5 ACCJ
MAX4256ESA -40°C to +85°C 8 SO
MAX4256EUA -40°C to +85°C 8 µMAX
MAX4257ESA -40°C to +85°C 8 SO
MAX4257EUA -40°C to +85°C 8 µMAX
Ordering Information (continued) Chip Information
MAX4250/MAX4251/MAX4255/MAX4256 TRANSISTOR
COUNT: 170
MAX4249/MAX4252/MAX4253/MAX4257 TRANSISTOR
COUNT: 340
MAX4254 TRANSISTOR COUNT: 680
VSS
IN-IN+
15VDD
OUT
MAX4250
MAX4250A
MAX4255
SOT23
TOP VIEW
2
34
OUT
N.C.VSS
1
2
8
7
SHDN
VDD
IN-
IN+
N.C.
μMAX/SO
3
4
6
5
MAX4251
MAX4256
INB-
INB+VSS
1
2
8
7
VDD
OUTBINA-
INA+
OUTA
μMAX/SO
3
4
6
5
MAX4252
MAX4257
1
2
3
4
5
10
9
8
7
6
VDD
OUTB
INB-
INB+VSS
INA+
INA-
OUTA
MAX4249
MAX4253
μMAX
SHDNBSHDNA
14
13
12
11
10
9
8
1
2
3
4
5
6
7
VDD
OUTB
INB-
INB+VSS
INA+
INA-
OUTA
MAX4249
MAX4253
N.C.
SHDNB
N.C.N.C.
SHDNA
N.C.
SO
14
13
12
11
10
9
8
1
2
3
4
5
6
7
OUTD
IND-
IND+
VSS
VDD
INA+
INA-
OUTA
MAX4254
INC+
INC-
OUTCOUTB
INB-
INB+
SO
Pin Configurations (continued)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
______________________________________________________________________________________ 15
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
16 ______________________________________________________________________________________
SOT-23 5L .EPS
E
1
1
21-0057
PACKAGE OUTLINE, SOT-23, 5L
8LUMAXD.EPS
PACKAGE OUTLINE, 8L uMAX/uSOP
1
1
21-0036 J
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
MAX
0.043
0.006
0.014
0.120
0.120
0.198
0.026
0.007
0.037
0.0207 BSC
0.0256 BSC
A2 A1
c
eb
A
L
FRONT VIEW SIDE VIEW
E H
0.6±0.1
0.6±0.1
Ø0.50±0.1
1
TOP VIEW
D
8
A2 0.030
BOTTOM VIEW
16∞
S
b
L
H
E
D
e
c
0∞
0.010
0.116
0.116
0.188
0.016
0.005
8
4X S
INCHES
-
A1
A
MIN
0.002
0.950.75
0.5250 BSC
0.25 0.36
2.95 3.05
2.95 3.05
4.78
0.41
0.65 BSC
5.03
0.66
6∞0∞
0.13 0.18
MAX
MIN
MILLIMETERS
- 1.10
0.05 0.15
α
α
DIM
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
10LUMAX.EPS
PACKAGE OUTLINE, 10L uMAX/uSOP
1
1
21-0061 I
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
TOP VIEW
FRONT VIEW
1
0.498 REF
0.0196 REF
S
SIDE VIEW
α
BOTTOM VIEW
0.037 REF
0.0078
MAX
0.006
0.043
0.118
0.120
0.199
0.0275
0.118
0.0106
0.120
0.0197 BSC
INCHES
1
10
L1
0.0035
0.007
e
c
b
0.187
0.0157
0.114
H
L
E2
DIM
0.116
0.114
0.116
0.002
D2
E1
A1
D1
MIN
-A
0.940 REF
0.500 BSC
0.090
0.177
4.75
2.89
0.40
0.200
0.270
5.05
0.70
3.00
MILLIMETERS
0.05
2.89
2.95
2.95
-
MIN
3.00
3.05
0.15
3.05
MAX
1.10
10
0.6±0.1
0.6±0.1
Ø0.50±0.1
H
4X S
e
D2
D1
b
A2 A
E2
E1 L
L1
c
α
GAGE PLANE
A2 0.030 0.037 0.75 0.95
A1
9LUCSP, 3x3.EPS
PACKAGE OUTLINE, 3x3 UCSP
21-0093
1
1
J
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
______________________________________________________________________________________ 17
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
18 ______________________________________________________________________________________
SOICN .EPS
PACKAGE OUTLINE, .150" SOIC
1
1
21-0041 B
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
TOP VIEW
FRONT VIEW
MAX
0.010
0.069
0.019
0.157
0.010
INCHES
0.150
0.007
E
C
DIM
0.014
0.004
B
A1
MIN
0.053A
0.19
3.80 4.00
0.25
MILLIMETERS
0.10
0.35
1.35
MIN
0.49
0.25
MAX
1.75
0.050
0.016L0.40 1.27
0.3940.386D
D
MINDIM
D
INCHES
MAX
9.80 10.00
MILLIMETERS
MIN MAX
16 AC
0.337 0.344 AB8.758.55 14
0.189 0.197 AA5.004.80 8
N MS012
N
SIDE VIEW
H 0.2440.228 5.80 6.20
e 0.050 BSC 1.27 BSC
C
HE
eBA1
A
D
0∞-8∞
L
1
VARIATIONS:
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
MAX4249–MAX4257
UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 19
© 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.
12L, USPC.EPS
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)