A4960-A Datasheet, PDF (1/34 Pages) Allegro MicroSystems – Automotive, Sensorless BLDC Controller

A4960
Automotive, Sensorless BLDC Controller
Features and Benefits
• 3-phase BLDC sensorless start-up and commutation
• Gate drive for N-channel MOSFETs
• Integrated PWM current limit
• 7 to 50 V supply voltage operating range
• Compatible with 3.3 V and 5 V logic
• Cross-conduction protection with adjustable dead time
• Charge pump for low supply voltage operation
• Extensive diagnostics output
• Low current sleep mode
Applications:
• Hydraulic pump
• Fuel pump
• Urea pump
• Blower fan
Package: 32-pin LQFP with exposed
thermal pad (suffix JP)
Not to scale
Description
The A4960 is a three-phase, sensorless, brushless DC
(BLDC) motor controller for use with external N-channel
power MOSFETs and is specifically designed for automotive
applications.
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. A programmable motor start-up scheme allows
the A4960 to be adjusted for a wide range of motor and load
combinations.
An external bootstrap capacitor is used to provide the above
battery supply voltage required for N-channel MOSFETs.
An automatic internal bootstrap charge management scheme
ensures that the bootstrap capacitor is always sufficiently
charged for safe operation of the power MOSFETs. The power
MOSFETs are protected from shoot-through by integrated
crossover control and adjustable dead time.
Integrated diagnostics provide indication of undervoltage,
overtemperature, and power bridge faults and can be configured
to protect the power MOSFETs under most short circuit
conditions. Detailed diagnostics are available as a serial data
word.
The A4960 is supplied in a 32-pin LQFP with exposed pad
for enhanced thermal dissipation (suffix JP). This package
is lead (Pb) free, with 100% matte-tin leadframe plating
(suffix –T).
Typical Application
V_BAT
A8450
Regulator
V_BAT
Micro-
controller
SPI
PWM
TACHO
RESET
FAULT
A4960
3-Phase
BLDC
Motor
A4960A-DS, Rev. 1