Bidirectional, Wide Positive and Negative Sensing Range, Current-Sense Amplifier with Fast PWM Rejection

The MAX49925 is a bidirectional current-sense amplifier (CSA) with an input common-mode range that extends from -40V to +76V, making it suitable for 48V HEV applications where there are large automotive transients.

This CSA has an extended input protection range of -42V to +80V against reverse-battery and high-voltage spikes. The wider input protection range also helps relax TVS requirements, leading to lower BOM cost and reduced component size.

The MAX49925 is well-suited for phase-current monitoring of inductive loads, such as motors and solenoids, where pulse-width modulation (PWM) is used to control the drive voltage and current.

The MAX49925 uses an improved technique to help reject common-mode input PWM edges with slew rates up to and beyond 500V/μs.

The MAX49925 operates over the full -40°C to +125°C temperature range and runs from a supply voltage of +2.7V to +5.5V. It is available in a 3mm x 3mm, 10-pin TDFN package with side-wettable flanks.

APPLICATIONS

* PWM H-Bridge Motor In-Line/In-Phase/Winding Current Sensing

* Solenoid Current Sensing

* Current Monitoring of Inductive Loads

* Battery Stack Monitors

* High Power DC Motors

* Automotive

* 48V Hybrid and Electric Vehicles (HEV)

* Fast, 500ns PWM Edge Recovery from >500V/ μs PWM Edges

* 140dB DC CMRR Rejection

* -40V to +76V Input Voltage Range

* -42V to +80V Protective Immunity

* 300kHz, -3dB Bandwidth

* On-the-Fly Programmable Gain with Two Input