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MAX9939_09 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – SPI Programmable-Gain Amplifier with Input VOS Trim and Output Op Amp
19-4329; Rev 1; 2/09
SPI Programmable-Gain Amplifier
with Input VOS Trim and Output Op Amp
General Description
The MAX9939 is a general-purpose, differential-input
programmable-gain amplifier (PGA) that is ideal for con-
ditioning a variety of wide dynamic range signals such
as those found in motor current-sense, medical instru-
mentation, and sonar data acquisition applications. It
features SPI™-programmable differential gains from
0.2V/V to 157V/V, input offset-voltage compensation, and
an output amplifier that can be configured either as a
high-order active filter or to provide a differential output.
The PGA is optimized for high-signal bandwidth and its
gain can be programmed to be 0.2V/V, 1V/V, 10V/V,
20V/V, 30V/V, 40V/V, 60V/V, 80V/V, 119V/V, and 157V/V.
Precision resistor matching provides extremely low gain
tempco and high CMRR. Although the MAX9939 oper-
ates from a single supply VCC between 2.9V to 5.5V, it
can process signals both above and below ground due
to the use of an input level-shifting amplifier stage.
Furthermore, its inputs are protected to ±16V, allowing it
to withstand fault conditions and signal overranges.
The output amplifier is designed for high bandwidth
and low-bias currents, making it ideal for use in multi-
ple-feedback active filter topologies that offer much
higher Qs and stopband attenuation than Sallen-Key
architectures.
The MAX9939 draws 3.4mA of quiescent supply current
at 5V, and includes a software-programmable shut-
down mode that reduces its supply current to only
13µA. The MAX9939 is available in a 10-pin µMAX®
package and operates over the -40°C to +125°C auto-
motive temperature range.
Applications
Sensorless Motor Control
Medical Signal Conditioning
Sonar and General Purpose Data Acquisition
Differential to Single-Ended Conversion
Differential-Input, Differential-Output Signal
Amplification
Sensor Interface and Signal Processing
SPI is a trademark of Motorola, Inc.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Features
o SPI-Programmable Gains: 0.2V/V to 157V/V
o Extremely Low Gain Tempco
o Integrated Amplifier for R/C Programmable Active
Filter
o Input Offset-Voltage Compensation
o Input Protection to ±16V
o 13µA Software Shutdown Mode
o -40°C to +125°C Operating Temperature Range
o 10-Pin µMAX Package
Ordering Information
PART
MAX9939AUB+
TEMP RANGE
-40°C to +125°C
PIN-PACKAGE
10 µMAX
+Denotes a lead(Pb)-free/RoHS-compliant package.
Pin Configuration
TOP VIEW
+
SCLK 1
DIN 2
GND 3
INA- 4
MAX9939
INA+ 5
10 CS
9 VCC
8 OUTA
7 INB
6 OUTB
μMAX
Functional Diagram appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products 1
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.