MAX4036 Datasheet, PDF (1/19 Pages) Maxim Integrated Products – Low IBIAS, +1.4V/800nA, Rail-to-Rail Op Amps with +1.2V Buffered Reference

19-3142; Rev 2; 11/04
Low I_BIAS, +1.4V/800nA, Rail-to-Rail Op Amps
with +1.2V Buffered Reference
General Description
The single MAX4036/MAX4037 and dual MAX4038/
MAX4039 operational amplifiers operate from a single
+1.4V to +3.6V (without reference) or +1.8V to +3.6V (with
reference) supply and consume only 800nA of supply
current per amplifier, and 1.1µA for the optional refer-
ence. The MAX4036/MAX4038 feature a common-mode
input voltage range from 0V to V_DD - 0.4V at V_DD = 1.4V.
The MAX4037/MAX4039 feature a 1.232V voltage refer-
ence capable of sourcing 100µA and sinking 20µA.
The MAX4036–MAX4039s’ rail-to-rail outputs drive 5kΩ
loads to within 25mV of the rails. Ultra-low supply current,
low operating voltage, and rail-to-rail outputs make the
MAX4036–MAX4039 ideal for use in single-cell lithium-ion
(Li+), or two-cell NiCd/NiMH/alkaline battery-powered
applications.
The MAX4036 is available in an SC70 package, the
MAX4037 in a SOT23 package, and the MAX4038/
MAX4039 in UCSP™, µMAX^®, and TDFN packages. All
devices are specified over the -40°C to +85°C extended
temperature range.
Applications
Battery-Powered/Solar-Powered Systems
Portable Medical Instrumentation
Pagers and Cell Phones
Micropower Thermostats and Potentiostats
Electrometer Amplifiers
Remote Sensor Amplifiers
Active Badges
pH Meters
µMAX is a registered trademark and UCSP is a trademark of
Maxim Integrated Products, Inc.
Functional Diagram
OUTA
MAX4039
INA-
INA+
REF
REF
VSS
VDD
OUTB
INB-
INB+
Features
♦ Ultra-Low 800nA per Amplifier Supply Current
♦ Ultra-Low 1.4V Supply Voltage Operation (1.8V for
MAX4037/MAX4039)
♦ Rail-to-Rail Outputs Drive 5kΩ and 5000pF Load
♦ 1.232V ±0.5%, 120ppm/°C (max) Reference
(MAX4037/MAX4039)
♦ No External Reference Bypass Capacitor
Required
♦ No Phase Reversal for Overdriven Inputs
♦ Low 1.0pA (typ) Input Bias Current
♦ Low 200µV Input Offset Voltage
♦ Unity-Gain Stable
♦ Available in Tiny UCSP, SC70, SOT23, TDFN, and
µMAX Packages
Ordering Information
PART
TEMP RANGE ^PIN-
PACKAGE
TOP
MARK
MAX4036EXK-T -40°C to +85°C 5 SC70-5
AFR
MAX4037EUT-T -40°C to +85°C 6 SOT23-6
ABRX
MAX4038ETA
-40°C to +85°C 8 TDFN-EP* AGO
MAX4038EUA
-40°C to +85°C 8 µMAX
—
MAX4038EBL-T -40°C to +85°C 9 UCSP-9
AEG
MAX4039EBL-T
MAX4039ETB
-40°C to +85°C 9 UCSP-9
-40°C to +85°C 10 TDFN-EP*
AEH
AAN
MAX4039EUB
-40°C to +85°C 10 µMAX
—
*EP = Exposed paddle.
Pin Configurations and Selector Guide appear at end of
data sheet.
Typical Operating Circuit
3V
V_DD
INA-
OUTA
INA+ _MAX4039
REF
INB-
INB+
OUTB
V_SS
SENSOR
ADC
THREE-ELECTRODE POTENTIOSTAT APPLICATION
________________________________________________________________ Maxim Integrated Products 1
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.