Allegro A4960 Sensorless BLDC Motor Driver
This is a driver for an A4960 sensorless brushless DC motor controller. It is developed for Micro Framework v.4.2 and based on manufacturers datasheet.
The code package consists of two parts:
• The driver itself, located in a4960 folder;
• Sample test program for FEZ Cerb 40: program.cs.
As A4960 is a pre-driver, it is controlling the external power circuit which best suits your motor. So, to run it properly, you need to design the schematics which would handle currents required by your motor. The scheme of the test device is shown in attached picture and described in readme.txt.
Another thing to mention for a power circuit design is that its very important that VBRG wire should be routed to the top of transistor bridge, LSS – to the bottom and CSP and CSM – to the ends of Rsense.
In most cases, the motor should run with default configuration settings. However, it may be needed to select a proper control PWM frequency for your motor – it sufficiently influences the operation stability, especially during the motor start sequence.
A few words about the test program. It initializes the controller and waits till the user presses the button. Then slowly increases the speed from 20% to 100% in 1% increments every 0.1 second and then continuously runs at 100% till the button is pressed again. Also, it counts and displays RPM ticks every second, outputs diagnostic faults, if any encountered and stops the motor in case of a fault.
A4960 datasheet: http://www.allegromicro.com/en/Products/Motor-Driver-And-Interface-ICs/Brushless-DC-Motor-Drivers/~/media/Files/Datasheets/A4960-Datasheet.ashx
A3940 datasheet: http://www.allegromicro.com/~/media/Files/Datasheets/A3940-Datasheet.ashx