19-1612; Rev 3; 4/02
Ultra-Small, 1.8V, µPower,
Rail-to-Rail I/O Op Amps
MAX4291/MAX4292/MAX4294
General Description
The MAX4291/MAX4292/MAX4294 family of micropow-
er operational amplifiers operates from a 1.8V to 5.5V
single supply or ±0.9V to ±2.75V dual supplies and has
Rail-to-Rail
®
input/output capabilities. These amplifiers
provide a 500kHz gain-bandwidth product and 120dB
open-loop voltage gain while using only 100µA of sup-
ply current per amplifier. The combination of low input
offset voltage (±200µV) and high open-loop gain makes
them ideal for low-power/low-voltage, high-precision
portable applications.
The MAX4291/MAX4292/MAX4294 have an input com-
mon-mode range that extends to each supply rail, and
their outputs swing to within 46mV of the rails with a 2kΩ
load. Although the minimum operating voltage is speci-
fied at 1.8V, these devices typically operate down to
1.5V. The combination of ultra-low-voltage operation, rail-
to-rail inputs/output, and low-power consumption makes
these devices ideal for any portable/two-cell battery-pow-
ered system.
The single MAX4291 is offered in an ultra-small 5-pin
SC70 package. The dual MAX4292 is offered in a
space-saving 8-bump, 1.5mm X 1.5mm footprint, ultra
chip-scale package (UCSP™).
Features
o
Ultra-Low Voltage Operation—Guaranteed Down
to 1.8V
o
100µA Supply Current per Amplifier
o
500kHz Gain-Bandwidth Product
o
120dB Open-Loop Voltage Gain (R
L
= 100kΩ)
o
0.017% Total Harmonic Distortion Plus Noise
(THD + N) at 1kHz
o
Rail-to-Rail Input Common-Mode Range
o
Rail-to-Rail Output Drives 2kΩ Load
o
No Phase Reversal for Overdriven Inputs
o
Unity-Gain Stable for Capacitive Loads up to 100pF
o
200µV Input Offset Voltage (MAX4292/MAX4294)
o
Single in Small 5-Pin SC70
o
Available in Ultra-Small Packages:
5-Pin SC70 (MAX4291)
8-Bump UCSP (MAX4292)
Applications
2-Cell Battery-Operated Systems
Portable Electronic Equipment
Battery-Powered Instrumentation
Digital Scales
Strain Gauges
Sensor Amplifiers
Cellular Phones
PART
MAX4291EXK-T
MAX4291EUK-T
MAX4292EBL-T*
MAX4292EUA
MAX4292ESA
MAX4294ESD
MAX4294EUD
Ordering Information
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
5 SC70-5
5 SOT23-5
8 UCSP-8
8 µMAX
8 SO
14 SO
14 TSSOP
TOP
MARK
AAD
ADML
AAJ
—
—
—
—
Pin Configurations
TOP VIEW
(BUMPS ON BOTTOM)
OUTA
V
CC
OUTB
*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.
Selector Guide
INA-
MAX4292
INB-
PART
MAX4291
INA+
V
EE
INB+
AMPLIFIERS
1
2
4
PIN-PACKAGE
5-pin SC70/SOT23
8-pin µMAX/SO/UCSP
14-pin SO/TSSOP
MAX4292
MAX4294
UCSP
Pin Configurations continued 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.
1
________________________________________________________________
Maxim Integrated Products
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.
Ultra-Small, 1.8V, µPower,
Rail-to-Rail I/O Op Amps
MAX4291/MAX4292/MAX4294
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
CC
to V
EE)
....................................................6V
All Other Pins ...................................(V
CC
+ 0.3V) to (V
EE
- 0.3V)
Current into IN_+, IN_- .....................................................
±
25mA
Output Short-Circuit Duration.....................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
5-Pin SC70 (derate 2.5mW/°C above +70°C) ................200mW
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 4.10mW/°C above +70°C)..............330mW
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 6.3mW/°C above +70°C) ............500mW
Operating Temperature Range............................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= 1.8V to 5.5V, V
EE
= V
CM
= 0, V
OUT
= V
CC
/2, R
L
= 100kΩ connected to V
CC
/2,
T
A
= +25°C,
unless otherwise noted.)
(Note 1)
PARAMETER
Supply Voltage Range
Quiescent Supply Current
(Per Amplifier)
Input Offset Voltage
Input Bias Current
Input Offset Current
Differential Input Resistance
Input Common-Mode Voltage
Range
SYMBOL
V
CC
I
Q
V
OS
I
B
I
OS
R
IN
V
CM
V
CC
= 1.8V
V
CC
= 5.0V
MAX4291
MAX4292/MAX4294
V
CC
= 5.0V, 0
≤
V
CM
≤
5.0V
V
CC
= 5.0V, 0
≤
V
CM
≤
5.0V
|V
IN+
- V
IN-
| < 10mV
Inferred from CMRR test
Tested for
0
≤
V
CM
≤
1.8V;
V
CC
= 1.8V
Common-Mode Rejection Ratio
Common-Mode Rejection Ratio
CMRR
Tested for
0
≤
V
CM
≤
5.0V,
V
CC
= 5.0V
PSRR
MAX4291
MAX4292/MAX4294
60
66
77
90
dB
90
100
dB
MAX4291
MAX4292/MAX4294
0
50
57
80
dB
80
CONDITIONS
Inferred from PSRR test
MIN
1.8
100
100
±400
±200
±15
±1
0.75
V
CC
TYP
MAX
5.5
210
255
±2500
±1200
±60
±7
UNITS
V
µA
µV
nA
nA
MΩ
V
Power-Supply Rejection Ratio
2
_______________________________________________________________________________________
Ultra-Small, 1.8V, µPower,
Rail-to-Rail I/O Op Amps
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 1.8V to 5.5V, V
EE
= V
CM
= 0, V
OUT
= V
CC
/2, R
L
= 100kΩ connected to V
CC
/2,
T
A
= +25°C,
unless otherwise noted.)
(Note 1)
PARAMETER
SYMBOL
CONDITIONS
R
L
= 100kΩ,
0.02V
≤
V
OUT
≤
V
CC
- 0.02V
V
CC
= 1.8V
R
L
= 2kΩ,
0.1V
≤
V
OUT
≤
V
CC
- 0.1V
Large-Signal Voltage Gain
A
V
R
L
= 100kΩ,
0.02V
≤
V
OUT
≤
V
CC
- 0.02V
V
CC
= 5.0V
R
L
= 2kΩ,
0.1V
≤
V
OUT
≤
V
CC
- 0.1V
Output-Voltage Swing High
Output-Voltage Swing Low
Output Short-Circuit Current
Channel-to-Channel Isolation
Gain-Bandwidth Product
Phase Margin
Gain Margin
Slew Rate
Input Voltage-Noise Density
Input Current-Noise Density
Capacitive-Load Stability
V
OH
V
OL
I
OUT(SC)
CH
ISO
GBWP
φ
M
GM
SR
e
n
i
n
f = 10kHz
f = 10kHz
A
VCL
= 1V/V, no sustained oscillations
Specified as
|V
CC
- V
OH
|
Specified as
|V
EE
- V
OL
|
R
L
= 100kΩ to V
CC
/2
R
L
= 2kΩ to V
CC
/2
R
L
= 100kΩ to V
CC
/2
R
L
= 2kΩ to V
CC
/2
80
120
2
15
25
46
20
83
500
65
12
0.2
70
0.05
100
20
40
80
120
mV
mV
mA
dB
kHz
degrees
dB
V/µs
nV/√Hz
pA/√Hz
pF
80
130
80
110
dB
MIN
80
TYP
120
MAX
UNITS
MAX4291/MAX4292/MAX4294
Sourcing or sinking
Specified at f = 10kHz (MAX4292/MAX4294 only)
ELECTRICAL CHARACTERISTICS
(V
CC
= 1.8V to 5.5V, V
EE
= V
CM
= 0, V
OUT
= V
CC
/2, R
L
= 100kΩ connected to V
CC
/2,
T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
(Note 1)
PARAMETER
Supply-Voltage Range
Quiescent Supply Current
(Per Amplifier)
Input Offset Voltage
SYMBOL
V
CC
I
Q
V
OS
V
CC
= 1.8V
V
CC
= 5.0V
MAX4291
MAX4292/MAX4294
CONDITIONS
Inferred from PSRR test
MIN
1.8
TYP
MAX
5.5
240
270
±3000
±2000
UNITS
V
µA
µV
_______________________________________________________________________________________
3
Ultra-Small, 1.8V, µPower,
Rail-to-Rail I/O Op Amps
MAX4291/MAX4292/MAX4294
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 1.8V to 5.5V, V
EE
= V
CM
= 0, V
OUT
= V
CC
/2, R
L
= 100kΩ connected to V
CC
/2,
T
A
= T
MIN
to T
MAX
, unless otherwise noted.)
(Note 1)
PARAMETER
Input Offset Voltage Drift
Input Bias Current
Input Offset Current
Input Common-Mode Voltage
Range
SYMBOL
TCV
OS
I
B
I
OS
V
CM
V
CC
= 5.0V, 0
≤
V
CM
≤
5.0V
V
CC
= 5.0V, 0
≤
V
CM
≤
5.0V
Inferred from CMRR test
Tested for
MAX4291
0
≤
V
CM
≤
1.8V,
MAX4292/MAX4294
V
CC
= 1.8V
Common-Mode Rejection Ratio
CMRR
Tested for
MAX4291
0
≤
V
CM
≤
5.0V,
MAX4292/MAX4294
V
CC
= 5.0V
Power-Supply Rejection Ratio
PSRR
R
L
= 100kΩ,
0.02V
≤
V
OUT
≤
V
CC
- 0.02V
R
L
= 2kΩ,
0.1V
≤
V
OUT
≤
V
CC
- 0.1V
R
L
= 100kΩ,
0.02V
≤
V
OUT
≤
V
CC
- 0.02V
R
L
= 2kΩ,
0.1V
≤
V
OUT
≤
V
CC
- 0.1V
R
L
= 100kΩ to V
CC
/2
R
L
= 2kΩ to V
CC
/2
R
L
= 100kΩ to V
CC
/2
R
L
= 2kΩ to V
CC
/2
60
62
75
80
80
dB
80
80
20
40
80
CONDITIONS
MIN
TYP
1.2
MAX
±90
±10
UNITS
µV/°C
nA
nA
V
0
50
V
CC
dB
53
dB
dB
dB
V
CC
= 1.8V
Large-Signal Voltage Gain
A
V
V
CC
= 5.0V
Output-Voltage Swing High
Output-Voltage Swing Low
V
OH
V
OL
Specified as
|V
CC
- V
OH
|
Specified as
|V
EE
- V
OL
|
mV
mV
120
Note 1:
All devices are 100% tested at T
A
= +25°C. All temperature limits are guaranteed by design.
4
_______________________________________________________________________________________
Ultra-Small, 1.8V, µPower,
Rail-to-Rail I/O Op Amps
Typical Operating Characteristics
(V
CC
= 2.4V, V
EE
= V
CM
= 0, V
OUT
= V
CC
/2, no load, T
A
= +25°C, unless otherwise noted.)
MAX4291/MAX4292/MAX4294
SUPPLY CURRENT PER AMPLIFIER
vs. TEMPERATURE
MAX4291 toc01
MINIMUM OPERATING VOLTAGE
vs. TEMPERATURE (PSRR
≥
80dB)
MAX4291 toc02
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
MAX4291 toc03
160
150
140
SUPPLY CURRENT (µA)
130
120
110
100
90
80
70
60
V
CC
= 1.8V
V
CC
= 5.5V
2.0
MINIMUM OPERATING VOLTAGE (V)
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
0
-150
V
CC
= 5.5V
-300
-450
-600
-750
-900
V
CC
= 2.4V
V
CC
= 1.8V
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
INPUT OFFSET VOLTAGE (µV)
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
INPUT BIAS CURRENT
vs. TEMPERATURE
MAX4291 toc04
INPUT BIAS CURRENT vs.
COMMON-MODE VOLTAGE (V
CC
= 1.8V)
MAX4291 toc05
INPUT BIAS CURRENT vs.
COMMON-MODE VOLTAGE (V
CC
= 5.5V)
30
INPUT BIAS CURRENT (nA)
20
10
0
-10
-20
-30
-40
MAX4291 toc06
35
30
INPUT BIAS CURRENT (nA)
25
20
V
CC
= 5.5V
15
10
5
0
V
CC
= 1.8V
40
30
INPUT BIAS CURRENT (nA)
20
10
0
-10
-20
-30
-40
-0.5
0
0.5
1.0
1.5
2.0
40
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
2.5
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
COMMON-MODE VOLTAGE (V)
COMMON-MODE VOLTAGE (V)
OUTPUT VOLTAGE SWING vs.
TEMPERATURE (R
L
= 100kΩ TO V
CC
/2)
MAX4291-07
OUTPUT VOLTAGE SWING vs.
TEMPERATURE (R
L
= 2kΩ TO V
CC
/2)
MAX4291-08
COMMON-MODE REJECTION RATIO
vs. TEMPERATURE
0
≤
V
CM
≤
V
CC
V
CC
= 1.8V
-70
-75
MAX4291 toc09
30
25
20
15
10
V
OH
= V
CC
- V
OUT
V
OL
= V
OUT
- V
EE
60
50
40
30
V
OH
= V
CC
- V
OUT
V
OL
= V
OUT
- V
EE
-65
OUTPUT VOLTAGE SWING (mV)
OUTPUT VOLTAGE SWING (mV)
V
OL
(V
CC
= 5.5V)
V
OL
(V
CC
= 5.5V)
CMRR (dB)
V
OH
(V
CC
= 5.5V)
V
OL
(V
CC
= 1.8V)
-80
-85
-90
-95
V
CC
= 5.5V
20
10
V
OH
(V
CC
= 1.8V)
0
V
OH
(V
CC
= 5.5V OR 1.8V)
5
0
-55
-25
5
35
V
OL
(V
CC
= 1.8V)
-100
-105
-55 -40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
65
95
125
-55
-25
5
35
65
95
125
TEMPERATURE (°C)
TEMPERATURE (°C)
_______________________________________________________________________________________
5