Document
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).
VBAT
A8450
Regulator
Typical Application
VBAT
Microcontroller
SPI
PWM TACHO RESET FAULT
A4960
3-Phase BLDC Motor
A4960A-DS, Rev. 3 MCO-0000174
April 25, 2019
A4960
Automotive, Sensorless BLDC Controller
Selection Guide
Part Number
Packing1
A4960KJPTR-A-T2
1500 pieces per 13-in. reel
1Contact Allegro™ for additional packing options
2The “-A” suffix indicates this is an enhanced EMC performance version.
Absolute Maximum Ratings1,2
Characteristic Load Supply Voltage Logic Supply Voltage Terminal VREG Terminal CP1
Symbol VBB VDD VREG VCP1
Notes
Terminal CP2
VCP2
Logic Inputs
Logic Outputs Terminal DIAG Terminal VBRG Terminals CA, CB, CC
VI
VO VDIAG VBRG VCx
Terminals STRN, SCK, SDI, PWM Terminal RESETN – can be pulled to VBB with >22 kΩ Terminals SDO, TACHO
Terminals GHA, GHB, GHC
VGHx
Terminals SA, SB, SC
VSx
Terminals GLA, GLB, GLC Terminal LSS Terminal REF Terminals CSP, CSM Terminal AGND
VGLx VLSS VREF VCSx
Connect directly to GND
Ambient Operating Temperature Range
TA
Temperature Range K; limited by power dissipation
Maximum Continuous Junction Temperature
TJ(max)
Transient Junction Temperature
Over temperature event not exceeding 10 s, TJt lifetime duration not exceeding 10 hours,
guaranteed by design characterization.
Storage Temperature Range
Tstg
1With respect to GND. Ratings apply when no other circuit operating constraints are present. 2Small “x” in pin names and symbols indicates a variable sequence character.
Rating –0.3 to 50 –0.3 to 6 –0.3 to 16 –0.3 to 16 VCP1 – 0.3 to VREG + 0.3 –0.3 to 6
–0.3 to 6
–0.3 to VDD + 0.3 –0.3 to VDD + 0.3
–5 to 55 –0.3 to VREG + 50
VCX – 16 to VCX + 0.3 VCX – 16 to VCX + 0.3 VREG – 16 to 18 VREG – 16 to 18 –0.3 to 6.5 –0.3 to 1
Unit V V V V
V
V
V
V V V V
V
V
V V V V
–40 to 150 150 175
–55 to 150
°C °C °C °C
Thermal Characteristics may require derating at maximum conditions, see application information
Characteristic
Symbol
Test Conditions*
Value
Package Thermal Resistance, Junction to Ambient
On 4-layer PCB based on JEDEC standard RθJA
On 2-layer PCB with 3 in.2 copper each side
23 44
Package Thermal Resistance, Junction to Pad
RθJP
2
*Additional thermal information available on the Allegro website
Unit ºC/W ºC/W
ºC/W
Allegro MicroSystems 955 Perimeter Road Manchester, NH 03103-3353 U.S.A. www.allegromicro.com
2
A4960
Automotive, Sensorless BLDC Controller
Table of Contents
Specifications Pin-out Diagram and Terminal List Functional Block Diagram Electrical Characteristics Table Timing Diagrams Operation Timing Diagrams Functional Description
Functional Description Input and Output Terminal Functions Motor Drive System Rotor position sensing using motor BEMF Commutation Blank Time BEMF Window BEMF Hysteresis Start-up Motor control Phase advance Power Supplies Gate Drives Gate drive voltage regulation Bootstrap charge management Low-side gate drive High-side gate drive Dead Time Sleep Mode and RESETN
2 4 5 6 10 10 12
12 12 13 13 14.