MAXIM MAX44261

19-5873; Rev 0; 6/11
EVALUATION KIT AVAILABLE
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
General Description
The MAX44260/MAX44261 offer a unique combination of
high speed, precision, low noise, and low-voltage operation making them ideally suited for a large number of
signal processing functions such as filtering and amplification of signals in portable and industrial equipment.
The amplifiers feature an input offset of less than 50FV
and a high-gain bandwidth product of 15MHz while
maintaining a low 1.8V supply rail. The devices’ rail-torail input/outputs and low noise guarantee maximum
dynamic range in demanding applications such as 12- to
14-bit SAR ADC drivers. Unlike traditional rail-to-rail input
structures, input crossover distortion is absent due to an
optimized input stage with an ultra-quiet charge pump.
The MAX44260 includes a fast-power-on shutdown mode
for further power savings. The MAX44261 offers a unique
on-demand calibration pin where the user can invoke
self-trimming of the input offset voltage.
Features
S Low 1.8V Supply Rail Over the -40°C to +125°C
Range
1.7V Supply Rail Over the 0°C to +70°C Range
S 15MHz Unity-Gain Bandwidth
S Low 12.7nV/√Hz Input Voltage-Noise Density
S Low 1.2fA/√Hz Input Current-Noise Density
S Low 50µV (max) VOS at +25°C
S On-Demand VOS Self-Calibration (MAX44261)
S 500fA Low Input Bias Current
S 750µA Quiescent Current per Amplifier
S < 1µA Supply Current in Shutdown
S Small, 2mm x 2mm SC70 Packages
S Low 110dB Total Harmonic Distortion
Applications
Notebooks
The family of parts operates from a supply range of 1.8V
to 5.5V over the -40NC to +125NC temperature range and
can operate down to 1.7V over the 0NC to +70NC temperature range. The MAX44260/MAX44261 are available
in small, 6-pin SC70 packages.
3G/4G Handsets
Portable Media Players
Portable Medical Instruments
Battery-Operated Devices
Analog-to-Digital Converter Buffers
Ordering Information appears at end of data sheet.
Transimpedance Amplifiers
General-Purpose Signal Processing
Typical Application Circuit
15nF
+3.3V
2.4kI
22kI
330pF
MAX44260
10kI
3.3nF
CORNER FREQUENCY = 10kHz
ADC
MAX11645
SALLEN-KEY FILTER
For related parts and recommended products to use with this part, refer to: www.maxim-ic.com/MAX44260.related
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For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
ABSOLUTE MAXIMUM RATINGS
IN+, IN-, OUT..................................(VSS - 0.3V) to (VDD + 0.3V)
VDD to VSS...............................................................-0.3V to +6V
SHDN, CAL..............................................................-0.3V to +6V
Output to Short-Circuit Ground Duration............................... 10s
Continuous Input Current into Any Pin............................. Q20mA
Continuous Power Dissipation (TA = +70NC)
SC70 (derate 3.1mW/NC above +70NC).......................245mW
Operating Temperature Range......................... -40NC to +125NC
Junction Temperature......................................................+150NC
Lead Temperature (soldering, 10s).................................+300NC
Soldering Temperature (reflow).......................................+260NC
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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
SC70
Junction-to-Ambient Thermal Resistance (BJA)..... 326.5NC/W
Junction-to-Case Thermal Resistance (BJC)..............115NC/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
ELECTRICAL CHARACTERISTICS
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are
at TA = +25NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
VDD
+ 0.1
V
DC CHARACTERISTICS
Input Voltage Range
VIN+ VIN-
Input Offset Voltage
VOS
Guaranteed by CMRR test
-0.1
10
TA = +25NC
VOS - TC
Input Bias Current
IB
Input Capacitance
CIN
Common-Mode Rejection Ratio
CMRR
TA = +25NC
0.8
5
0.01
0.5
100
TA = -40NC to +125NC
dB
VCM = -0.1V to (VDD + 0.1V)
75
90
100
115
91
100
AOL
0.4V P VOUT P VDD - 0.4V, ROUT = 600I
0.4V P VOUT P VDD - 0.4V, ROUT = 32I
80
Output Short-Circuit Current
ISC
To VDD or VSS
50
VOL VSS
ROUT = 10kI
20
ROUT = 600I
50
VDD VOH
400
dB
mA
700
ROUT = 10kI
10
ROUT = 600I
40
ROUT = 32I
pA
pF
0.4V P VOUT P VDD - 0.4V, ROUT = 10kI
ROUT = 32I
FV/NC
4
Open-Loop Gain
Output Voltage Swing
FV
500
TA = -40°C to +125°C
Input Offset Voltage Drift
50
100
TA = -40°C to +125°C after calibration
400
mV
800
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MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are
at TA = +25NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
AC CHARACTERISTICS
Input Voltage-Noise Density
en
f = 10kHz
12.7
nV/√Hz
Input Current-Noise Density
in
f = 10kHz
1.2
fA/√Hz
15
MHz
7
V/Fs
1.7
µs
Gain-Bandwidth Product
Slew Rate
GBWP
SR
VOUT = 2VP-P, VDD = 3.3V, AV = 1V/V,
CL = 30pF (load)
Settling Time
Capacitive Loading
Total Harmonic Distortion
CLOAD
THD
No sustained oscillation
300
pF
f = 10kHz, VO = 2VP-P, AV = 1, ROUT = 10kI
-110
dB
1
µs
DVOUT = 0.2V, VDD = 3.3V, AV = 1V/V;
RS = 20Ω, CL = 1nF (load)
Output Transient Recovery Time
POWER-SUPPLY CHARACTERISTICS
Power-Supply Range
Power-Supply Rejection Ratio
Quiescent Current
Shutdown Supply Current
Shutdown Input Low
Shutdown Input High
VDD
PSRR
Guaranteed by PSRR
1.8
5.5
TA = 0NC to +70NC
1.7
5.5
VCM = VDD/2
82
IDD
ISHDN
95
750
MAX44260/MAX44261 only
VIL
VIH
V
dB
1200
µA
1
µA
0.7
V
1.3
V
Shutdown Turn-On Time
tSHDN
25
µs
Output Leakage Current in
Shutdown
ISHDN
100
pA
Shutdown Input Bias Current
IIL/IIH
Turn-On Time
tON
MAX44260
1
MAX44261
0.1
10
µA
ms
Note 2: All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.
����������������������������������������������������������������� Maxim Integrated Products 3
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Typical Operating Characteristics
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are at
TA = +25NC, unless otherwise noted. All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.)
INPUT OFFSET VOLTAGE
vs. SUPPLY VOLTAGE
20
TA = -40°C
0
-20
TA = +25°C
0
0.5
1.0
1.5
2.0
2.5
20
TA = +25°C
0
-20
-40
TA = +125°C
-60
MAX44260 toc03
15
10
5
-100
3.5
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0
5.5
-15 -10
-5
0
5
10
15
20
SUPPLY VOLTAGE (V)
INPUT OFFSET VOLTAGE (µV)
INPUT OFFSET DRIFT HISTOGRAM
INPUT BIAS CURRENT
vs. COMMON-MODE VOLTAGE
OUTPUT-VOLTAGE LOW
vs. OUTPUT SINK CURRENT
(VOL - VEE, VCC = 1.8V)
12
10
8
6
4
80
60
40
TA = +25°C
20
0
-20
TA = -40°C
-40
-60
2
-80
0
-100
-1.5 -1 -0.5
0
0.50 1.00
-1.8 -1.3 -0.8 -0.3 0.25 0.75 1.25
INPUT OFFSET DRIFT (µV/°C)
TA = +85°C
TA = +125°C
200
25
MAX44260 toc06
14
100
180
OUTPUT-VOLTAGE LOW (mV)
MAX44260 toc04
16
-2
20
COMMON-MODE VOLTAGE (V)
18
PERCENT OCCURRENCE (%)
3.0
INPUT BIAS CURRENT (pA)
-0.5
40
25
-80
TA = +125°C
-60
TA = -40°C
60
MAX44260 toc05
-40
80
MAX44260 toc02
40
INPUT VOS HISTOGRAM
100
INPUT OFFSET VOLTAGE (µV)
MAX44260 toc01
INPUT OFFSET VOLTAGE (µV)
60
PERCENT OCCURRENCE (%)
INPUT OFFSET VOLTAGE
vs. COMMON-MODE VOLTAGE
160
140
120
TA = +25°C
100
80
TA = +125°C
60
TA = -40°C
40
20
0
-0.5
0
0.5
1.0
1.5
2.0
2.5
COMMON-MODE VOLTAGE (V)
3.0
3.5
0.1
1
10
OUTPUT SINK CURRENT (mA)
100
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MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Typical Operating Characteristics (continued)
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are at
TA = +25NC, unless otherwise noted. All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.)
OUTPUT-VOLTAGE LOW
vs. OUTPUT SINK CURRENT
(VOL - VEE, VCC = 5V)
TA = +25°C
120
100
80
TA = +125°C
60
40
20
1
10
OUTPUT SINK CURRENT (mA)
140
TA = +25°C
120
100
80
TA = +125°C
60
40
20
TA = -40°C
0
0.1
140
TA = +25°C
120
100
80
TA = +125°C
60
TA = -40°C
40
20
1
10
OUTPUT SINK CURRENT (mA)
1
10
OUTPUT SOURCE CURRENT (mA)
80
100
TA = +125°C
60
TA = -40°C
40
0.1
180
160
140
SUPPLY CURRENT vs. SUPPLY VOLTAGE
TA = +25°C
120
100
80
TA = +125°C
60
TA = -40°C
40
0.1
1
10
OUTPUT SOURCE CURRENT (mA)
100
1
10
OUTPUT SOURCE CURRENT (mA)
900
MAX44260 toc11
200
850
TA = +25°C
800
TA = +125°C
750
700
TA = -40°C
650
0
0.1
100
100
20
0
TA = +25°C
120
0
0.1
OUTPUT-VOLTAGE HIGH (mV)
160
140
OUTPUT-VOLTAGE HIGH
vs. OUTPUT SOURCE CURRENT
(VCC - VOH, VCC = 5V)
MAX44260 toc10
OUTPUT-VOLTAGE HIGH (mV)
180
160
20
TA = -40°C
OUTPUT-VOLTAGE HIGH
vs. OUTPUT SOURCE CURRENT
(VCC - VOH, VCC = 3.3V)
200
180
0
100
MAX44260 toc09
160
200
MAX44260 toc12
140
180
SUPPLY CURRENT (µA)
160
200
MAX44260 toc08
OUTPUT-VOLTAGE LOW (mV)
180
OUTPUT-VOLTAGE LOW (mV)
MAX44260 toc07
200
OUTPUT-VOLTAGE HIGH
vs. OUTPUT SOURCE CURRENT
(VCC - VOH, VCC = 1.8V)
OUTPUT-VOLTAGE HIGH (mV)
OUTPUT-VOLTAGE LOW
vs. OUTPUT SINK CURRENT
(VOL - VEE, VCC = 3.3V)
100
600
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
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MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Typical Operating Characteristics (continued)
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are at
TA = +25NC, unless otherwise noted. All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.)
SHUTDOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGE
(VSHDN = VEE)
0.6
0.5
TA = -40°C
0.4
TA = +25°C
0.3
0.2
MAX44260 toc15
100
-20
80
-40
CMRR (dB)
0.7
0
MAX44260 toc14
TA = +125°C
OPEN-LOOP GAIN (dB)
0.9
0.8
120
MAX44260 toc13
SHUTDOWN SUPPLY CURRENT (µA)
1.0
COMMON-MODE REJECTION RATIO
vs. FREQUENCY
OPEN-LOOP GAIN
vs. FREQUENCY
60
-60
40
-80
20
-100
0.1
0
0.001 0.01
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
1
10
100
1k
10k 100k
0
1
10
100
1k
10k
FREQUENCY (kHz)
FREQUENCY (kHz)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
DC CMRR AND PSRR
vs. TEMPERATURE
INPUT VOLTAGE-NOISE DENSITY
vs. FREQUENCY
REJECTION RATIO (dB)
-40
-60
-80
DC CMRR
-94
-96
-98
-100
DC PSRR
-100
-120
0.1
1
10
100
FREQUENCY (kHz)
1k
10k
100k
100k
MAX44260 toc18
-92
500
INPUT-VOLTAGE NOISE DENSITY (nV/√Hz)
-90
MAX44260 toc16
-20
0.01
0.01
SUPPLY VOLTAGE (V)
0
PSRR (dB)
-120
0
MAX44260 toc17
1.5
450
400
350
300
250
200
150
100
50
0
-50
-25
0
25
50
75
TEMPERATURE (°C)
100
125
0.01
0.1
1
10
100
1k
10k
FREQUENCY (kHz)
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MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Typical Operating Characteristics (continued)
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are at
TA = +25NC, unless otherwise noted. All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.)
TOTAL HARMONIC DISTORTION
vs. INPUT AMPLITUDE
(f = 10kHz, VCC = 5.5V, AV = 1V/V)
INPUT CURRENT-NOISE DENSITY
vs. FREQUENCY
MAX44260 toc19
4.5
4.0
110
3.5
3.0
2.5
2.0
105
100
95
1.5
90
1.0
85
0.5
0
4s/div
115
THD (dB)
0.5µV/div
120
MAX44260 toc20
INPUT-CURRENT NOISE DENSITY (fA/√Hz)
5.0
10
100
1000
10k
100k
80
0
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION
vs. FREQUENCY (VIN = 2VP-P)
-85
THD (dB)
-90
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT AMPLITUDE (V)
SMALL-SIGNAL TRANSIENT RESPONSE
LARGE-SIGNAL TRANSIENT RESPONSE
MAX44260 toc23
MAX44260 toc22
-80
MAX44260 toc21
0.1Hz TO 10Hz OUTPUT-VOLTAGE NOISE
INPUT
50mV/div
VCC/2
MAX44260 toc24
INPUT
1V/div
VCC/2
-95
-100
VCC = 5.5V
OUTPUT
500mV/div
VCC/2
-105
OUTPUT
50mV/div
VCC/2
-110
VCC = 3.3V
-115
-120
1
10
100
1k
10k
100k
200ns/div
100ns/div
FREQUENCY (Hz)
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MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Typical Operating Characteristics (continued)
(VDD = 3.3V, VSS = 0V, VIN+ = VIN- = VDD/2, RL = 10kI to VDD/2, VCAL = VSHDN = VDD, TA = -40NC to +125NC. Typical values are at
TA = +25NC, unless otherwise noted. All devices are 100% production tested at TA = +25NC. Temperature limits are guaranteed by design.)
STABILITY vs. CAPACITIVE LOAD
AND ISOLATION RESISTANCE
OVERSHOOT (%)
14
12
10
8
6
4
2
0
100
1k
10k
100k
100k
STABLE
MAX44260 toc27
16
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
10k
RESISTIVE LOAD (I)
18
STABILITY vs. CAPACITIVE
AND RESISTIVE LOAD
MAX44260 toc26
MAX44260 toc25
20
ISOLATION RESISTANCE (I)
PERCENT OVERSHOOT
vs. LOAD RESISTANCE (VIN = 100mVP-P)
UNSTABLE
1k
100
STABLE
10
UNSTABLE
1
0
LOAD RESISTANCE (I)
500 1000 1500 2000 2500 3000 3500 4000
100
1k
POWER-UP TIME
100k
TURN-ON TIME FROM SHUTDOWN
MAX44260 toc28
MAX44260 toc29
VCC
2V/div
SHDN
2V/div
GND
VSS
OUTPUT
500mV/div
10k
CAPACITIVE LOAD (pF)
CAPACITIVE LOAD (pF)
OUTPUT
500mV/div
VSS
GND
4ms/div
4µs/div
����������������������������������������������������������������� Maxim Integrated Products 8
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Pin Configurations
TOP VIEW
NOT TO SCALE
+
IN+
1
VSS
IN-
+
MAX44260
6
VDD
IN+
1
2
5
SHDN
VSS
3
4
OUT
IN-
MAX44261
6
VDD
2
5
CAL
3
4
OUT
SC70
SC70
Pin Description
PIN
MAX44260
MAX44261
NAME
FUNCTION
1
1
IN+
—
—
INA+
Positive Input
Positive Input A
—
—
INB+
Positive Input B
2
2
VSS
Negative Power Supply. Bypass with a 0.1FF capacitor to ground.
3
3
IN-
Negative Input
—
—
INA-
Negative Input A
—
—
INB-
Negative Input B
Output
4
4
OUT
—
—
OUTA
Output A
—
—
OUTB
Output B
—
5
CAL
5
—
6
6
SHDN
VDD
Active-Low Calibrate Input
Active-Low Shutdown
Positive Power Supply. Bypass with a 0.1FF capacitor to ground.
����������������������������������������������������������������� Maxim Integrated Products 9
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Detailed Description
Crossover Distortion
These op amps feature a low-noise integrated charge
pump that creates an internal voltage rail 1V above
VDD, which is used to power the input differential
pair of PMOS transistors as shown in Figure 1. Such
a unique architecture eliminates crossover distortion common in traditional CMOS input architecture
(Figure 2), especially when used in a noninverting
configuration, such as for Sallen-Key filters.
The MAX44260/MAX44261 are high-speed low-power op
amps ideal for signal processing applications due to the
device’s high precision and low-noise CMOS inputs. The
devices self-calibrate on power-up to eliminate effects of
temperature and power-supply variation.
The MAX44260 also features a low-power shutdown
mode that greatly reduces quiescent current while the
device is not operational and recovers in 30µs.
The charge pump’s operating frequency lies well above
the unity-gain frequency of the amplifier. Thanks to its highfrequency operation and ultra-quiet circuitry, the charge
pump generates little noise, does not require external
components, and is entirely transparent to the user.
The MAX44261 features a user-selectable self-calibration
input that shuts down the device and allows it to be recalibrated at any time. The calibration routine takes 10ms.
INTERNAL
CHARGE
PUMP
MAX44260 INPUTS STRUCTURE
STANDARD INPUT STRUCTURE
Figure 1. Comparing the Input Structure of the MAX44260 to Standard Op-Amp Inputs
AMPLIFIER OUTPUT
CROSSOVER
DISTORTION
MAX44261
TIME
Figure 2. Crossover Distortion of Typical Amplifiers
���������������������������������������������������������������� Maxim Integrated Products 10
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Applications Information
and retains its power-up trim settings. Figure 3 shows
that the device also recovers from shutdown in under
30Fs.
Power-Up Autotrim
The MAX44261 features a recalibrate input that acts the
same as the shutdown mode of the MAX44260. However,
when the input is pulled low, the device goes through a
self-calibration sequence again (Figure 3).
The ICs feature an automatic trim that self-calibrates the
VOS of these devices to less than 100FV of input offset
voltage on power-up. This self-calibration feature allows
the device to eliminate input offset voltage effects due
to power supply and operating temperature variation
simply by cycling its power. The autotrim sequence takes
approximately 10ms to complete and is triggered by an
internal power-on-reset (POR) circuitry. During this time,
the inputs and outputs are put into high impedance and
left unconnected. The MAX44261 can also be forced into
a self-calibration cycle by pulling the CAL input low for
1ms. This input also puts the part into shutdown mode.
The shutdown logic levels of the devices are independent of supply, allowing the shutdown feature of the
device to operate off of a 1.8V or 3.3V microcontroller,
regardless of supply voltage.
Rail-to-Rail Input/Output
The input voltage range of the ICs extends 100mV
above VDD and below VSS. The wide input commonmode voltage range allows the op amp to be used as
a buffer and as a differential amplifier in a wide-variety
of signal processing applications. Output voltage high/
low is designed to be only 50mV above VSS and below
VDD allowing maximum dynamic range in single-supply
applications. The high output current and capacitance
drive capability of the devices make them ideal as an
ADC driver and a line driver.
Shutdown Operation
The MAX44260 features an active-low shutdown mode
that puts both inputs and outputs into high impedance
and substantially lowers the quiescent current to less
than 1FA. Putting the output into high impedance allows
multiple outputs to be multiplexed onto a single output
line without the additional external buffers. The device
does not self-calibrate when exiting shutdown mode
VDD
VSHDN/VCAL
0V
VDD/2
FAST RECOVERY
AMPLIFIER
ACTIVE
MAX44260
OUTPUT
0V
VDD/2
MAX44261
OUTPUT
0V
AUTOTRIM
SEQUENCE
RECALIBRATED
AMPLIFIER
ACTIVE
30µs
10ms
Figure 3. CAL vs. SHDN Input Operation
���������������������������������������������������������������� Maxim Integrated Products 11
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Input Bias Current
The ICs feature a high-impedance CMOS input stage
and a specialized ESD structure that allows low-input
bias current operation at low-input, common-mode voltages. Low-input bias current is useful when interfacing
with high-ohmic sensors. It is also beneficial for designing transimpedance amplifiers for photodiode sensors.
This makes these devices ideal for ground-referenced
medical and industrial sensor applications.
Active Filters
The MAX44260/MAX44261 are ideal for a wide variety
of active filter circuits that make use of their wide bandwidth, rail-to-rail input/output stages and high-impedance
CMOS inputs. The Typical Application Circuit shows an
example Sallen-Key active filter circuit with a corner
frequency of 10kHz. At low frequencies, the amplifier
behaves like a simple low-distortion noninverting buffer, while its high bandwidth gives excellent stopband
attenuation above its corner frequency. See the Typical
Application Circuit.
Driver for Interfacing with
the MAX11645 ADC
The ICs’ tiny size and low noise makes them a good fit for
driving 12- to 16-bit resolution ADCs in space-constrained
applications. The Typical Application Circuit shows the
MAX44260 amplifier output connected to a lowpass filter
driving the MAX11645 ADC. The MAX11645 is part of a
family of 3V and 5V, 12-bit and 10-bit, 2-channel ADCs.
The MAX11645 offers sample rates up to 94ksps and
measures two single-ended inputs or one differential
input. These ADCs dissipate 670FA at the maximum
sampling rate, but just 6FA at 1ksps and 0.5FA in shutdown. Offered in the ultra-tiny, 1.9mm x 2.2mm WLP and
FMAX-8 packages, the MAX11645 ADCs are an ideal fit
to pair with the MAX44260/MAX44261 amplifiers in portable applications.
Where higher resolution is required, refer to the MAX1069
(14-bit) and MAX1169 (16-bit) ADC families.
Chip Information
Ordering Information
PROCESS: BiCMOS
PART
TEMP RANGE
PINPACKAGE
TOP
MARK
MAX44260AXT+
-40NC to 125NC
6 SC70
+AEB
MAX44261AXT+
-40NC to 125NC
6 SC70
+AEC
+Denotes a lead(Pb)-free/RoHS-compliant package.
���������������������������������������������������������������� Maxim Integrated Products 12
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Package Information
For the latest package outline information and land patterns (footprints), 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.
PACKAGE TYPE
PACKAGE CODE
OUTLINE NO.
LAND PATTERN NO.
6 SC70
X6SN+1
21-0077
90-0189
���������������������������������������������������������������� Maxim Integrated Products 13
MAX44260/MAX44261
1.8V 15MHz Low-Offset,
Low-Power, Rail-to-Rail I/O Op Amps
Revision History
REVISION
NUMBER
REVISION
DATE
0
6/11
DESCRIPTION
Initial release
PAGES
CHANGED
—
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. The parametric values (min and max limits) shown in the Electrical
Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2011
Maxim Integrated Products 14
Maxim is a registered trademark of Maxim Integrated Products, Inc.