General Description
The MAX49921 is high-precision, unidirectional currentsense
amplifier (CSA) with an operating input commonmode
range from 0 to +70V, though the device is protected
against input common-mode voltages down to -42V
and up to +80V, thus providing protection against reversebattery
and high-voltage spikes. The MAX49921 is wellsuited
for current monitoring of inductive loads, such as
DC motors and solenoids, where common-mode voltages
can become negative due to inductive kickback, reversebattery
conditions, or transient events.
The low input offset of ±0.5μV (typ) and low gain error of
±0.05% (typ) make this device best-suited for high-precision
current measurements.
The MAX49921 operates from a supply voltage of +2.7V
to +5.5V with a typical quiescent supply at 0.7mA. This
device is specified over the full -40°C to +125°C automotive
temperature range and is AEC-Q100 qualified. The
MAX49921 is offered in a 2mm x 3mm, 8-pin, side-wettable
TDFN package with gain options of 20V/V and
50V/V.

Applications
● Solenoid Current Sensing
● Battery Current Monitoring
● Current Monitoring of Inductive Loads
● High- and Low-Side Precision Current Sensing
● Supercapacitor Charge/Discharge Monitoring
● Precision High-Voltage Current Monitoring
● Automotive Current Sensing

Benefits and Features
● AEC-Q100 Qualified for Automotive Applications
● ±0.5μV (typ) Input Offset Voltage
● ±0.05% (typ) Gain Error
● 0 to +70V Input Voltage Range
● -42V to +80V Protective Immunity
● 65kHz, -3dB Bandwidth
● 140dB DC CMRR
● Gain Options: 20V/V, 50V/V
● Rail-to-Rail Output
● 2mm x 3mm, 8-Pin TDFN Package
● -40°C to +125°C Automotive Temperature Range