General Description

The MAX49921 is high-precision, unidirectional current-

sense amplifier (CSA) with an operating input common-

mode range from 0 to +70V, though the device is pro-

tected against input common-mode voltages down to -42V

and up to +80V, thus providing protection against reverse-

battery and high-voltage spikes. The MAX49921 is well-

suited for current monitoring of inductive loads, such as

DC motors and solenoids, where common-mode voltages

can become negative due to inductive kickback, reverse-

battery 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-preci-

sion 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 automo-

tive temperature range and is AEC-Q100 qualified. The

MAX49921 is offered in a 2mm x 3mm, 8-pin, side-wet-

table 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

Ordering Information appears at end of data sheet.

Simplified Block Diagram

LEVEL

SHIFTING

GND

MAX49921

MAX49921

RS-

RS+

OUT

Click here to ask an associate for production status of specific part numbers.

MAX49921

0 to 70V, High-Precision Current-Sense

Amplifier

EVALUATION KIT AVAILABLE

Ordering Information appears at end of data sheet.

19-100848; Rev 1; 9/21

© 2021 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners.

One Analog Way, Wilmington, MA 01887 U.S.A. | Tel: 781.329.4700 | © 2021 Analog Devices, Inc. All rights reserved.