A4962: Sensorless BLDC Controller

Description

The A4962 is a three-phase, sensorless, brushless DC (BLDC) motor controller for use with external complementary P-channel and N-channel power MOSFETs and is specifically designed for automotive applications.

The A4962 can be used as a stand-alone controller communicating directly with an electronic control unit (ECU) or it can be used in a close coupled system with a local microcontroller (MCU).

The motor is driven using block commutation (trapezoidal drive) where phase commutation is determined, without the need for independent position sensors, by monitoring the motor back-EMF (bemf). The sensorless start-up scheme allows the A4962 to operate over a wide range of motor and load combinations.

Dedicated circuits allow the A4962 to operate over a wide range of motor speeds, from less than 100 rpm to in excess of 30,000 rpm, depending on the supply voltage and motor capability.

Several operational modes are available including duty-cycle (voltage) control, current (torque limit) control and closed loop speed control. Operating mode and control parameters can be altered through an SPI compatible serial interface. Motor operation is controlled by a programmable PWM input that can be used to define the motor operating state and provide the proportional input for the selected operating mode. Integrated diagnostics provide indication of under voltage, over temperature and power bridge faults and can protect the power switches under most short circuit conditions. Faults are indicated by a single open drain output than can be used to pull the PWM input low.

The A4962 is provided in a small, thermally enhanced 20-pin TSSOP with exposed thermal pad.

Top Features

  • Three phase sensorless BLDC motor control FET driver
  • Logic level P-N gate drive (P high-side, N low-side)
  • 4.2 V to 50 V supply range
  • Simple block commutation for maximum torque
  • Sensorless (bemf sensing) start-up and commutation
  • Programmable operating modes:
    • Integrated Speed Control
    • PWM Duty Cycle Control
    • Current mode control
  • Cross-conduction prevention
  • Wide speed range capability
  • Peak current limiting
  • Single low frequency PWM control input
  • Single Open Drain Fault output
  • SPI compatible interface providing:
    • Configuration and control
    • Programmable dead time
    • Programmable phase advance
    • Detailed diagnostic reporting

APPLICATIONS

  • Automotive Fuel, Oil, and Urea Pumps
  • Automotive Fans and Blowers

Part Number Specifications and Availability

Part Number Package Type Temperature RoHS
Compliant
Part Composition /
RoHS Data
Comments Samples Check Stock
A4962KLPTR-T 20-lead TSSOP -40°C to 150°C Yes View Data Contact your
local sales rep
Check
Distributor Stock
APEK4962KLP-01-T DEMO BOARD -40°C to 150°C No -- Contact your
local sales rep
Check
Distributor Stock

Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro’s product can reasonably be expected to cause bodily harm.

Packaging

A4962 Packages

Design Support Tools

NOTE: When ordering, please also request APEK-USBCBLE-T