A3921 Datasheet (PDF) Download
Allegro MicroSystems
A3921

Overview

The A3921 is a full-bridge controller for use with external N‑channel power MOSFETs and is specifically designed for automotive applications with high-power inductive loads, such as brush DC motors. A unique charge pump regulator provides full (>10 V) gate drive for battery voltages down to 7 V and allows the A3921 to operate with a reduced gate drive, down to 5.5 V.

  • High current gate drive for N-channel MOSFET full bridge
  • High-side or low-side PWM switching
  • Charge pump for low supply voltage operation
  • Top-off charge pump for 100% PWM
  • Cross-conduction protection with adjustable dead time
  • 5.5 to 50 V supply voltage range
  • Integrated 5 V regulator
  • Diagnostics output
  • Low current sleep mode
  • AEC-Q100 qualified Package: 28-pin TSSOP with exposed thermal pad (suffix LP) Not to scale