Rainbow Electronics MAX4249, MAX4257 User Manual

General Description

The MAX4249–MAX4257 low-noise, low-distortion oper­ational amplifiers offer Rail-to-Rail®outputs and single­supply 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 shut­down 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-to­rail and their input common-mode voltage range
includes ground. The MAX4250–MAX4254 are unity­gain stable with a gain-bandwidth product of 3MHz.
The MAX4249/MAX4255/MAX4256/MAX4257 are inter­nally 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-pin
ultra chip-scale package (UCSP™) and the MAX4253 is
available in a 10-pin UCSP.

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 (1kΩ load)

♦ 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 AV≥ 10V/V
(MAX4249/MAX4255/MAX4256/MAX4257)

♦ Excellent DC Characteristics

VOS= 70µV
I

BIAS

= 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 4; 1/02

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.

Rail-to-Rail is a registered trademark of Nippon Motorola, Ltd.

UCSP is a trademark of Maxim Integrated Products, Inc.

Pin Configurations continued at end of data sheet.

Pin Configurations

Ordering Information

TOP VIEW

(BUMPS ON BOTTOM)

12 3

V

OUTA

A

B

C

INA-

INA+

DD

MAX4252

V

SS

OUTB

INB-

INB+

PART TEMP RANGE

MAX4249ESD

MAX4249EUB -40°C to +85°C 10 µMAX —

MAX4250EUK-T

-40°C to +85°C 14 SO —

-40°C to +85°C 5 SOT23-5 ACCI

PIN­PACKAGE

TOP

MARK

A4

A3

A2

OUTB

V

OUTA

A1

INB-

B1

DD

C1

MAX4253

C2 C3

INA-

INB+

INA+

SHDNB

V

C4

SHDNA

B4

SS

UCSP

UCSP

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, V

OUT

= VDD/2, RLtied to VDD/2, SHDN = VDD, TA= -40°C to +85°C, unless otherwise noted. Typical

values are at T

A

= +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 (VDDto VSS) ......................+6.0V to -0.3V

Analog Input Voltage (IN_+, IN_-)....(V

DD

+ 0.3V) to (VSS- 0.3V)

SHDN Input Voltage ......................................6.0V to (V

SS

- 0.3V)

Output Short-Circuit Duration to Either Supply ..........Continuous

Continuous Power Dissipation (T

A

= +70°C)

5-Pin SOT23 (derate 7.1mW/°C above +70°C)...........571mW

8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW

8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW

8-Pin UCSP (derate 4.7mW/°C above +70°C) ............379mW

10-Pin 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

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

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 rec­ommended in the industry-standard specification, JEDEC 020A, paragrah 7.6, Table 3 for IR/VPR and Convection Reflow.
Preheating is required. Hand or wave soldering is not allowed.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Voltage Range V

Quiescent Supply Current Per
Amplifier

Input Offset Voltage (Note 5) V

Input Offset Voltage Tempco TCV

Input Bias Current I

Input Offset Current I

Differential Input Resistance R

Input Common-Mode Voltage
Range

Common-Mode Rejection Ratio CMRR VSS - 0.2V ≤ VCM ≤ VDD - 1.1V 70 115 dB

Power-Supply Rejection Ratio PSRR VDD = 2.4 to 5.5V 75 100 dB

Large-Signal Voltage Gain A

Output Voltage Swing V

I

OS

V

OUT

(Note 4) 2.4 5.5 V

DD

VDD = 3V 400

Q

Shutdown mode (SHDN = VSS) (Note 2) 0.5 1.5

OS

OS

(Note 6) ±1 ±100 pA

B

(Note 6) ±1 ±100 pA

IN

Guaranteed by CMRR test -0.2 V

CM

RL = 10kΩ to VDD/2;
V

= 25mV to V

OUT

V

RL = 1kΩ to VDD/2;
V

= 150V to V

OUT

|V

- V

IN+

R

IN-

= 10kΩ to V

L

VDD = 5V 420 575Normal mode

V

| ≥ 10mV

DD

= 5V, UCSP only 420 655

DD

±0.07 ±0.75 mV

0.3 µV/°C

1000 GΩ

DD

DD

/2

- 4.97V

- 4.75V

V

- V

DD

OH

V

- V

OL

SS

80 116

80 112

825

720

- 1.1 V

DD

µA

dB

mV

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= 5V, VSS= 0, VCM= 0, V

OUT

= VDD/2, RLtied to VDD/2, SHDN = VDD, TA= -40°C to +85°C, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Notes 2, 3)

D

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Output Voltage Swing V

Output Short-Circuit Current I

Output Leakage Current I

SHDN Logic Low V

SHDN Logic High V

SHDN Input Current IIL/I

Input Capacitance 11 pF

Gain-Bandwidth Product GBW

Slew Rate SR

Peak-to-Peak Input-Noise
Voltage

Input Voltage-Noise Density e

Input Current-Noise Density i

OUT

SC

LEAK

e

n

V

- V

DD

|V

IN+

= 1kΩ to V

R

L

- V

| ≥ 10mV,

IN-

DD

/2

OH

V

- V

OL

SS

Shutdown mode (SHDN = VSS),
V

= V

to V

OUT

(Note 2) 0.2 X V

IL

(Note 2) 0.8 X V

IH

SHDN = V

IH

SS

SS

(Note 2)

DD

= V

(Note 2) 0.5 1.5 µA

DD

MAX4250–MAX4254

MAX4249/MAX4255/MAX4256/MAX4257

MAX4250–MAX4254

MAX4249/MAX4255/MAX4256/MAX4257

f = 0.1Hz to 10Hz

P-P

f = 10Hz

f = 1kHz

n

f = 30kHz

n

f = 1kHz

77 200

47 100

68 mA

0.001 1.0 µA

DD

3

22

0.3

2.1

760 nV

2.7

8.9

7.9

0.5 fA/√Hz

D

nV/√Hz

mV

V

V

MHz

V/µs

P-P

Total Harmonic Distortion Plus
Noise

Capacitive-Load Stability

Gain Margin GM

Phase Margin ΦM

THD + N

MAX4250–MAX4254

= 1V/V, V

A

V

R

= 1kΩ to GND

L

OUT

= 2V

(Note 7)

MAX4249/MAX4255/

P-P

,

f = 1kHz

f = 20kHz

f = 1kHz

0.0004

0.006

0.0012

MAX4256/MAX4257

= 1V/V, V

A

V

= 1kΩ to GND (Note 7)

R

L

No sustained oscillations

OUT

= 2V

P-P

,

f = 20kHz

0.007

400 pF

MAX4250–MAX4254, AV = 1V/V 10

MAX4249/MAX4255/MAX4256/MAX4257,
A

= 10V/V

V

12.5

MAX4250–MAX4254, AV = 1V/V 74

MAX4249/MAX4255/MAX4256/MAX4257,
A

= 10V/V

V

68

%

dB

degrees

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= 5V, VSS= 0, VCM= 0, V

OUT

= VDD/2, RLtied to VDD/2, SHDN = VDD, TA= -40°C to +85°C, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Notes 2, 3)

Note 2: SHDN is available on the MAX4249/MAX4251/MAX4253/MAX4256 only.
Note 3: All device specifications are 100% tested at T

A

= +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.

Settling Time

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

MAX4250–MAX4254 6.7

To 0.01%,
= 2V step

V

OUT

MAX4249/MAX4255/
MAX4256/MAX4257

1.6

µs

I

Delay Time to Shutdown t

Delay Time to Enable t

Power-Up Delay Time t

SH

EN

PU

VDD = 5% of

normal
operation

V

OUT = 2.5V,

V

OUT settles to

0.1%

V

DD = 0 to 5V step, VOUT stable to 0.1%

MAX4251/MAX4253 0.8

MAX4249/MAX4256 1.2

MAX4251/MAX4253 8

MAX4249/MAX4256 3.5

6µs

µs

µs

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

_______________________________________________________________________________________ 5

Typical Operating Characteristics

(VDD= 5V, VSS= 0, VCM= V

OUT

= VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements,

T

A

= +25°C, unless otherwise noted.)

MAX4251/MAX4256

INPUT OFFSET VOLTAGE DISTRIBUTION

40

35

30

25

20

15

NUMBER OF UNITS

10

5

0

-95

-75

-55

-35

-13

7

284969

VOS (µV)

90

400 UNITS

V

CM

= +25°C

T

A

110

131

152

= 0

172

MAX4249-57 TOC01

192

OFFSET VOLTAGE

vs. TEMPERATURE

250

VCM = 0

200

150

100

50

(µV)

0

OS

V

-50

-100

-150

-200

-250

-40 0-20 20 40 60 80

TEMPERATURE (°C)

MAX4249-57 TOC02

200

150

100

INPUT OFFSET VOLTAGE (µV)

INPUT OFFSET VOLTAGE vs.

INPUT COMMON-MODE VOLTAGE

50

0

-50

-0.5 1.50.5 2.5 3.5 4.5
INPUT COMMON-MODE VOLTAGE (V)

VDD = 3V VDD = 5V

MAX4249-57 TOC03

OUTPUT VOLTAGE vs.

OUTPUT LOAD CURRENT

0.6

VDD = 3V OR 5V

= ±10mV

V

DIFF

0.5

0.4

0.3

0.2

OUTPUT VOLTAGE (V)

0.1

0

04312 5678910

OUTPUT LOAD CURRENT (mA)

VDD - V

OH

V

LARGE-SIGNAL VOLTAGE GAIN

vs. OUTPUT VOLTAGE SWING

140

130

120

110

(dB)

100

V
A

90

80

70

60

50

0 10050 150 200 250

V

OUT

R

SWING FROM EITHER SUPPLY (mV)

R

L

R

L

RL = 2kΩ

REFERENCED TO GND

L

OL

= 200kΩ

= 20kΩ

VDD = 3V

MAX4249-57 TOC04

MAX4249-57 TOC07

OUTPUT VOLTAGE SWING (VOH)

0.10

0.09

0.08

0.07

(V)

0.06

OH

- V

0.05

DD

V

0.04

0.03

0.02

0.01

0

-40 0-20 20 6040 80

vs. TEMPERATURE

RL = 1kΩ

TEMPERATURE (°C)

LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING

140

130

120

110

(dB)

V

A

100

90

80

70

60

0 50 100 150 200 250

V

OUT

= 20kΩ

R

L

R

= 2kΩ

L

R

REFERENCED TO GND

L

SWING FROM EITHER SUPPLY (mV)

RL = 10kΩ

RL = 100kΩ

= 200kΩ

R

L

VDD = 3V

MAX4249-57 TOC05

MAX4249-57 TOC08

OUTPUT VOLTAGE SWING (VOL)

0.06

0.05

0.04

(V)

OL

0.03

V

0.02

0.01

0

-40 0-20 20 6040 80

vs. TEMPERATURE

R

L

TEMPERATURE (°C)

LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING

= 200kΩ

R

L

= 20kΩ

R

L

90

80

70

60

50

0 10050 150 200 250

V

SWING FROM EITHER SUPPLY (mV)

OUT

R

R

REFERENCED TO GND

L

(dB)

V

A

140

130

120

110

100

= 1kΩ

RL = 10kΩ

R

= 100kΩ

L

= 2kΩ

L

VDD = 5V

MAX4249 -57TOC06

MAX4249-57 TOC09

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= 5V, VSS= 0, VCM= V

OUT

= VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements,

T

A

= +25°C, unless otherwise noted.)

LARGE-SIGNAL VOLTAGE GAIN
vs. OUTPUT VOLTAGE SWING

150

R

= 200kΩ

L

140

130

120

110

(dB)

V

A

100

90

80

70

60

50

0 10050 150 200 250

V

SWING FROM EITHER SUPPLY (mV)

OUT

= 20kΩ

R

L

RL = 2kΩ

R

REFERENCED TO GND

L

LARGE-SIGNAL VOLTAGE GAIN

vs. TEMPERATURE

RL REFERENCED TO VDD/2

= 5V

V

DD

= 100kΩ

R

L

V

= 10mV

OUT

TO 4.99mV

RL = 1kΩ
V

= 150mV

OUT

TO 4.75mV

TEMPERATURE (°C)

R

= 10kΩ

L

= 20mV

V

OUT

TO 4.975mV

MAX4249-57 TOC11

VDD = 5V

MAX4249-57 TOC10

125

120

115

(dB)

V

A

110

105

100

-40 0-20 20 6040 80

SUPPLY CURRENT AND SHUTDOWN

SUPPLY CURRENT vs. SUPPLY VOLTAGE

440

PER AMPLIFIER

420

SHDN = V

400

380

360

SUPPLY CURRENT (µA)

340

320

1.8 2.82.3 3.3 3.8 4.3 4.8 5.3 5.5

DD

SUPPLY VOLTAGE (V)

SHDN = V

MAX4249-57 TOC13

SS

MAX4250–MAX4254

GAIN AND PHASE vs. FREQUENCY

60

50

40

30

20

10

GAIN (dB)

0

-10

-20

-30

-40
100 10k 100k 1M1k 10M

GAIN

PHASE

FREQUENCY (Hz)

MAX4249-57 TOC16

VDD = 3V, 5V

R

= 50kΩ

L

= 20pF

C

L

= 1000

A

V

0.6

0.5

0.4

0.3

0.2

0.1

0

180

144

108

72

36

0

-36

-72

-108

-144

-180

2000

1000

400

SUPPLY CURRENT (µA)

SHUTDOWN SUPPLY CURRENT (µA)

100

0.001 0.1 10.01 5

MAX4249/MAX4255/MAX4256/MAX4257

60

50

40

30

20

10

GAIN (dB)

0

PHASE (DEGREES)

-10

-20

-30

-40
100 10k 100k 1M1k 10M

SUPPLY CURRENT

vs. OUTPUT VOLTAGE

VDD = 5V

VDD = 3V

OUTPUT VOLTAGE (V)

GAIN AND PHASE vs. FREQUENCY

VDD = 3V, 5V

= 50kΩ

R

L

= 20pF

C

L

= 1000

A

V

FREQUENCY (Hz)

MAX4249-57 TOC17

GAIN

PHASE

MAX4249-57 TOC14

180

144

108

72

36

0

-36

-72

-108

-144

-180

PHASE (DEGREES)

SUPPLY CURRENT AND SHUTDOWN

SUPPLY CURRENT vs. TEMPERATURE

460

PER AMPLIFIER

440

420

400

380

SUPPLY CURRENT (µA)

360

340

-40 0-20 20 6040 80

SHDN = V

DD

SHDN = V

TEMPERATURE (°C)

SS

INPUT OFFSET VOLTAGE

vs. SUPPLY VOLTAGE

180

160

RL REFERENCED TO GND

140

120

(µV)

OS

V

100

R

L

= 10kΩ

80

60

40

1.8 2.3 2.8 3.3 3.8 4.3 4.8 5.3
SUPPLY VOLTAGE (V)

MAX4250–MAX4254

POWER-SUPPLY REJECTION RATIO

0

VDD = 3V, 5V

-10

-20

-30

-40

-50

-60

PSRR (dB)

-70

-80

-90

-100

-110
1 1k 10k 100k 1M10 100 10M

vs. FREQUENCY

PSRR+

PSRR-

FREQUENCY (Hz)

MAX4249-57 TOC12

V

OUT

R

= 100kΩ

L

V

= VDD/2

R

= 1kΩ

L

0.376

0.375

0.374

SHUTDOWN SUPPLY CURRENT (µA)

0.373

= 0

CM

MAX4249-57 TOC15

MAX4249-57 TOC18

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

_______________________________________________________________________________________ 7

Typical Operating Characteristics (continued)

(VDD= 5V, VSS= 0, VCM= V

OUT

= VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements,

T

A

= +25°C, unless otherwise noted.)

OUTPUT IMPEDANCE

vs. FREQUENCY

1000

AV = 10 (MAX4249/MAX4255/

MAX4256/MAX4257)

100

MAX4249-57 TOC19

10

OUTPUT IMPEDANCE (Ω)

1

A

= 1 (MAX4250–MAX4254)

V

0.1
1k 10k 100k 1M 10M

FREQUENCY (Hz)

MAX4250–MAX4254

FFT OF DISTORTION AND NOISE

0

V

-20

-40

OUT

= 2V

P-P

RL = 1kΩ

= 1kHz

f

O

= 1

A

V

MAX4249-57 TOC22

-60

f

O

-80

-100

AMPLITUDE (dBc)

HD2

-120

HD4

HD5

HD3

-140

-160
10 5k 10k

15k

20k

FREQUENCY (Hz)

MAX4250–MAX4254

TOTAL HARMONIC DISTORTION PLUS NOISE

= 10kΩ

R

L

R

P-P

DD

= 100kΩ

L

)

= 3V)

V

OUT

R

L

MAX4249-57 TOC25

vs. OUTPUT VOLTAGE SWING (V

10

1

0.1

RL = 1kΩ

V

11kΩ

IN

100kΩ

THD + N (%)

0.01
= 10

A

V

= 3kHz

f

O

FILTER BW = 30kHz

0.001
0213

OUTPUT VOLTAGE (V

INPUT VOLTAGE-N0ISE DENSITY

vs. FREQUENCY

30

25

20

15

10

5

Vn-EQUIVALENT INPUT NOISE-VOLTAGE (nV/√Hz)

0

10 100 1k 10k 100k

FREQUENCY (Hz)

MAX4249/MAX4255/MAX4256/MAX4257

FFT OF DISTORTION AND NOISE

20

V

OUT

0

-20

-40

-60

-80

AMPLITUDE (dBc)

-100

V

IN

f

O

HD2

HD3

11kΩ

100kΩ

V

10kΩ

O

-120

-140
10 5k 10k

15k

FREQUENCY (Hz)

MAX4249/MAX4255/MAX4256/MAX4257

TOTAL HARMONIC DISTORTION PLUS NOISE

vs. OUTPUT VOLTAGE SWING

1

A

= 10

V

0.1

THD + N (%)

0.01

fO = 3kHz, FILTER BW = 30kHz

0.001
03412 5

V

IN

100kΩ

11kΩ

fO = 20kHz, FILTER BW = 80kHz

OUTPUT VOLTAGE (V

)

P-P

= 4V

fO = 1kHz

20k

V
R

P-P

OUT

L

MAX4249-57 TOC20

200nV/div

MAX4249-57 TOC23

MAX4249-57 TOC26

THD + N (%)

0.0001

10

1

0.1

THD + N (%)

0.01

0.001

1

0.1

0.01

0.001

V

DD

V

P-PNOISE

= 3V OR 5V

0.1Hz TO 10Hz

= 760nV

P-P

P-P

NOISE

1s/div

MAX4250–MAX4254

TOTAL HARMONIC DISTORTION PLUS NOISE

100kΩ

RL = 10kΩ

P-P

DD

)

= 5V)

vs. OUTPUT VOLTAGE (V

AV = 10

= 3kHz

f

O

FILTER BW = 30kHz

RL = 1kΩ

021 345

V

IN

11kΩ

R

= 100kΩ

L

OUTPUT VOLTAGE (V

MAX4250–MAX4254

TOTAL HARMONIC DISTORTION

PLUS NOISE vs. FREQUENCY

V

IN

R2

R1

R1 = 560Ω, R2 = 53kΩ

R1 = 5.6kΩ, R2 = 53kΩ

A

= 1

V

FILTER BW = 22kHz
R

10 1k100 10k

FREQUENCY (Hz)

V

R

L

A

= 100

V

A

= 10

V

= 10kΩ TO GND

L

= 2V

V

O

OUT

V

R

O

L

P-P

MAX4249-57 TOC21

MAX4249-57 TOC24

MAX4249-57 TOC27

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

8 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= 5V, VSS= 0, VCM= V

OUT

= VDD/2, input noise floor of test equipment =10nV/√Hz for all distortion measurements,

T

A

= +25°C, unless otherwise noted.)

MAX4250–MAX4254

TOTAL HARMONIC DISTORTION

0.1

0.01

0.001

THD + N (%)

0.0001

PLUS NOISE vs. FREQUENCY

FILTER BW = 80kHz

= 1

A

V

RL = 1kΩ

= 2V

V

OUT

P-P

RL TO VDD/2

10 1k100 10k

FREQUENCY (Hz)

MAX4249/MAX4255/MAX4256/MAX4257

LARGE-SIGNAL PULSE RESPONSE

2V

V

OUT

200mV/div

= 3V

V

DD

= 10kΩ

R

L

= 100pF

C

1V

L

= 100mV PULSE

V

IN

= 10

A

V

2µs/div

MAX4250–MAX4254

LARGE-SIGNAL PULSE RESPONSE

1.5V

MAX4249-57 TOC29

R

TO GND

L

TO V

R

L

MAX4249-57 TOC28

V

OUT

200mV/div

DD

0.5V

VDD = 3V

= 10kΩ

R

L

C

= 100pF

L

= 1V PULSE

V

IN

2µs/div

MAX4249/MAX4255/MAX4256/MAX4257

SMALL-SIGNAL PULSE RESPONSE

MAX4249-57 TOC31

50mV/div

1.6V

V

1.5V

OUT

V

= 3V

DD

= 10kΩ

R

L

= 100pF

C

L

V

= 10mV PULSE

IN

= 10

A

V

2µs/div

MAX4249-57 TOC32

MAX4250–MAX4254

SMALL-SIGNAL PULSE RESPONSE

0.6V

V

OUT

20mV/div

V

0.5V

= 3V

DD

= 10kΩ

R

L

= 100pF

C

L

V

= 100V PULSE

IN

2µs/div

CHANNEL SEPARATION vs. FREQUENCY

140

130

120

110

100

90

80

CHANNEL SEPARATION (dB)

70

0

1k 100k 1M10k 10M

FREQUENCY (Hz)

MAX4249-57 TOC30

MAX4249-57 TOC33

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-to­digital 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 ouput operation,
drive loads as low as 1kΩ while maintining DC accura-

cy, and can drive capactive loads up to 400pF without
oscillation. The input common-mode voltage range
extends from V

DD

- 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 low­power shutdown mode, which reduces the supply cur­rent to 0.5µA and disables the outputs.

Pin Description

PIN/BUMP

M A X4 2 5 0 /

M A X4 2 5 5

5-Pin

SOT23

1 6 1, 7 A1, A3 A1, C1 1, 9 1, 13

244C2B44411

3 3 3, 5 C1, C3 A3, C3 3, 5 3, 11

4 2 2, 6 B1, B3 A2, C2 2, 6 2, 12

5 7 8 A2 B1 8 14 4

— 8 ——A4, C4 — 5, 9 —

— 1, 5 ————

———B2 B2, B3 —— — —

M A X4 2 5 1 /

M A X4 2 5 6

8-Pin

SO/µMAX

M A X4 2 5 2 /

M A X4 2 5 7

8-Pin

SO/µMAX

M A X4 2 5 2

8-Pin

UCSP

10-Pin

UCSP

M A X4 2 4 9 /

M A X4 2 5 3

10-Pin

µMAX

M A X4 2 5 4

1 4 - Pin SO14-Pin

5, 7,
8, 10

SO

1, 7, 8,

14

3, 5, 10,

12

2, 6, 9,

13

— N.C.

NAME FUNCTION

OUT, OUTA,

OUTB,
OUTC,

OUTD

V

SS

IN + , IN A+ ,

IN B+ , IN C + ,

IN D +

IN-, INA-,

INB-,

INC-, IND-

V

DD

SHDN,

SHDNA,

SHDNB

Amplifier Output

Negative Supply.
Connect to
ground for single­supply operation

Noninverting
Amplifier Input

Inverting
Amplifier Input

Positive Supply

Shutdown Input,
Connect to V
or leave
unconnected for
normal operation
(amplifier(s)
enabled).

No Connection.
Not internally
connected.

Not populated
with solder
sphere

DD

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 closed­loop gain, the smaller the THD generated, especially
when driving heavy resistive loads. Large-value feed­back 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 out­put. 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 con­stant 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 ther­mal noise contribution is affected by the parallel combi­nation 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 cir­cuit 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 R

F

= 100kΩ, RG=

1.1kΩ, the e

n

is low (9nV/√Hz).

Figure 1. Adding Feed-Forward Compensation

Figure 2a. Pulse Response with No Feed-Forward
Compensation

Figure 2b. Pulse Response with 10pF Feed-Forward
Compensation

C

Z

R

F

R

G

V

IN

AV = 2V/V
R

= RG = 10kΩ

F

100mV

0

2µs/div

AV = 2
R

= RG = 100kΩ

F

= 11pF

C

100mV

Z

V

IN

0

V

OUT

2µs/div

VIN =

50mV/div

V

=

OUT

100mV/div

50mV/div

100mV/div

V

OUT

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

______________________________________________________________________________________ 11

Using a Feed-Forward Compensation

Capacitor, C

Z

The amplifier’s input capacitance is 11pF. If the resis­tance 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:

C

Z

= 11 x (RF/ RG) [pF]

In the unity-gain stable MAX4250–MAX4254, the use of
a proper C

Z

is most important for AV= 2V/V, and A

V

=

-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 for­mula above achieves a higher bandwidth at the
expense of reduced phase and gain margin. As a gen­eral 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 capa­bility with ground-sensing input and rail-to-rail output
operation. With their low distortion, low noise and low­power 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 common­mode 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 A

V

= 10V/V. The output

swings to within 8mV of the supplies with a 10kΩ load,
making the devices ideal in low-supply-voltage applica­tions.

Output Loading and Stability

Even with their low quiescent current of 400µA, these
amplifiers can drive 1kΩ loads while maintaining excel­lent DC accuracy. Stability while driving heavy capaci­tive loads is another key feature.

Figure 3. Overdriven Input Showing No Phase Reversal

Figure 4. Rail-to-Rail Output Operation

Figure 5. Capacitive-Load Driving Circuit

R

ISO

V

IN

4.25V

0

4.45V

0

MAX4250
MAX4251
MAX4252
MAX4253
MAX4254

20µs/div

AV = 1

VDD = 5V

RL = 10kΩ

V

OUT

V

IN

-200mV

V

OUT

C

L

5V

0

VDD = 5V

RL = 10kΩ
A

= 10

V

f = 1kHz

200µs/div

V

OUT

1V/div

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 isolat­ing 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 corre­sponding 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 VDDpin. 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, min­imize PC board trace lengths and resistor leads, and
place external components close to the op amp’s pins.

UCSP Package Consideration

For general UCSP package information and PC layout
considerations, please refer to the Maxim Application
Note (Wafer-Level Ultra-Chip-Board-Scale-Package).

UCSP Reliability

The UCSP represents a unique packaging form factor
that may not perform equally to a packaged product
through traditional mechanical reliability tests. UCSP
reliability is integrally linked to the user’s assembly
methods, circuit board material, and usage environ­ment. The user should closely review these areas when
considering use of a UCSP. Performance through oper­ating life test and moisture resistance remains uncom­promised as it is primarily determined by the
wafer-fabrication process. Mechanical stress perfor­mance is a greater consideration for a UCSP. UCSPs
are attached through direct solder contact to the user’s
PC board, foregoing the inherent stress relief of a pack­aged product lead frame. Solder-joint contact integrity
must be considered. Table 1 shows the testing done to
characterize the UCSP reliability performance. In con­clusion, the UCSP is capable of performing reliably
through environmental stresses as indicated by the
results in the table. Additional usage data and recom­mendations are detailed in the UCSP application note,
which can be found on Maxim’s website at
www.maxim-ic.com.

Figure 6. Isolation Resistance vs. Capacitive Loading to
Minimize Peaking (<2dB)

Figure 7. Peaking vs. Capacitive Load

Figure 8. MAX4250-4254 Unity-Gain Bandwidth vs. Capacitive
Load

160

140

120

100

(Ω)

80

ISO

R

60

40

20

0

10 10,000

NOTE: USING AN ISOLATION RESISTOR REDUCES PEAKING.

SHADED AREA INDICATES
STABLE OPERATION
WITH NO NEED FOR
ISOLATION RESISTOR.

CAPACITIVE LOADING (pF)

1000100

4.5

4.0

3.5

3.0

2.5

2.0

1.5
SHADED AREA INDICATES

1.0

UNITY-GAIN BANDWIDTH (MHz)

STABLE OPERATION
WITH NO NEED FOR

0.5
ISOLATION RESISTOR.

0

10 10,000

CAPACITIVE LOAD (pF)

NOTE: R

CHOSEN FOR PEAKING <2dB.

ISO

V

= 3V

DD

1000100

25

MAX4250–MAX4254 (A
MAX4249/MAX4255–MAX4257 (A

R

= 0

ISO

20

SHADED AREA INDICATES

15

STABLE OPERATION
WITH NO NEED FOR
ISOLATION RESISTOR.

10

PEAKING (dB)

5

0

10 10,000

= 1)

V

CAPACITIVE LOAD (pF)

1000100

= 10)

V

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

______________________________________________________________________________________ 13

Typical Operating Circuit

Table 1. Reliability Test Data

5V

V

50kΩ

2

V

IN

3

5kΩ

MAX4256

4

7

6

8

AIN

SHDN

DD

MAX195

(16-BIT ADC)

V

SS

-5V

DOUT

SCLK

CS

REF

SERIAL
INTERFACE

4.096V

SHDN

TEST CONDITIONS DURATION

Temperature Cycle -35°C to +85°C, -40°C to +100°C 150 cycles, 900 cycles 0/10, 0/200

T

Operating Life
Moisture Resistance -20°C to +60°C, 90% RH 240h 0/10
Low-Temperature Storage -20°C 240h 0/10
Low-Temperature Operational -10°C 24h 0/10

Solderability 8h steam age — 0/15
ESD ±2000V, Human Body Model — 0/5

High-Temperature Operating
Life

= +70°C

A

= +150°C

T

J

240h 0/10

168h 0/45

NO. OF FAILURES PER

SAMPLE SIZE

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

14 ______________________________________________________________________________________

Selector Guide

Ordering Information (continued)

*UCSP reliability is integrally linked to the user’s assembly
methods, circuit board material, and environment. Refer to the
UCSP Reliability Notice in the UCSP Reliability section of this
data sheet for more information.

Chip Information

MAX4250/MAX4251/MAX4255/MAX4256 TRANSISTOR
COUNT: 170

MAX4249/MAX4252/MAX4253/MAX4257 TRANSISTOR
COUNT: 340

MAX4254 TRANSISTOR COUNT: 680

G A IN

PART

MAX4249 22 10 2 Yes 10-pin µMAX, 14-pin SO

MAX4250 3 1 1 — 5-pin SOT23
MAX4251 3 1 1 Yes 8-pin µMAX/SO
MAX4252 3 1 2 — 8-pin µMAX/SO, 8-pin UCSP

MAX4253 3 1 2 Yes

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

B A N D WID T H

( M H z)

MINIMUM

STABLE

GAIN (V/V)

NO. OF

AMPLIFIERS PER

PACKAGE

SHUTDOWN

MODE

PIN-PACKAGE

10-pin µMAX, 14-pin SO,
10-pin UCSP

PART TEMP RANGE

MAX4251ESA

MAX4251EUA -40°C to +85°C 8µMAX —

MAX4252EBL-T*

MAX4252ESA -40°C to +85°C 8 SO —

MAX4252EUA -40°C to +85°C 8 µMAX —

MAX4253EBC-T*

MAX4253EUB -40°C to +85°C 10 µMAX —

MAX4253ESD -40°C to +85°C 14 SO —

MAX4254ESD

MAX4255EUK-T

MAX4256ESA

MAX4256EUA -40°C to +85°C 8 µMAX —

MAX4257ESA

MAX4257EUA -40°C to +85°C 8 µMAX —

-40°C to +85°C 8 SO —

-40°C to +85°C 8 UCSP-8 AAO

-40°C to +85°C 10 UCSP-10 AAK

-40°C to +85°C 14 SO —

-40°C to +85°C 5 SOT23-5 ACCJ

-40°C to +85°C 8 SO —

-40°C to +85°C 8 SO —

PIN­PACKAGE

TOP

MARK

Pin Configurations (continued)

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

______________________________________________________________________________________ 15

TOP VIEW

15V

OUT

MAX4250

2

V

SS

MAX4255

34

SOT23

1

OUTA

INA-

2

INA+

SS

MAX4249

3

MAX4253

4

5

µMAX

1

DD

N.C.

IN-

2

MAX4251
MAX4256

3

IN+

4

IN-IN+

SS

µMAX/SO

1

V

10

DD

9

OUTB

8

INB-

7

INB+V

6

SHDNBSHDNA

OUTA

INA-

INA+

N.C.

SHDNA

2

3

4

5

6

7

MAX4249
MAX4253

SS

87SHDN

V

DD

OUT

6

N.C.V

5

V

14

13

OUTB

12

INB-

11

INB+V

10

N.C.

9

SHDNB

8

N.C.N.C.

OUTA

1

2

87V

DD

OUTBINA-

MAX4252

INA+

MAX4257

3

4

SS

INB-

6

INB+V

5

µMAX/SO

1

DD

OUTA

INA-

INA+

V

INB+

INB-

2

3

4

DD

MAX4254

5

6

7

OUTD

14

IND-

13

IND+

12

V

11

SS

10

INC+

9

INC-

8

OUTCOUTB

SO

SO

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

16 ______________________________________________________________________________________

Package Information

SOT5L.EPS

8LUMAXD.EPS

Package Information (continued)

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

______________________________________________________________________________________ 17

10LUMAX.EPS

9LUCSP, 3x3.EPS

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,
Low-Distortion, Rail-to-Rail Op Amps

18 ______________________________________________________________________________________

Package Information (continued)

SOICN.EPS

MAX4249–MAX4257

UCSP, Single-Supply, Low-Noise,

Low-Distortion, Rail-to-Rail Op Amps

Package Information (continued)

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

© 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

12L, USPC.EPS