MA782 NVM Writes

Motor Drivers/Sensors
1

I am working on a design in which, due to board constraints, I do not have access to the NVM busy pin signal. Instead, I have implemented a timer that prevents the code from starting another NVM write for 30ms following every NVM write. The datasheet specifies a minimum NVM register store time of 23ms, however, it does not list a maximum. My questing is, what is the maximum possible NVM write time (for a single register) required at 22C +/-5C?

I ask because I appear to be having occasional NVM write failures and perhaps, I need to wait more than 30ms.

2

Hello Rob,

Sorry for the delayed reply. The 30ms wait time should be enough.

I have some questions about your case:

  • Could you please provide more details about which operations are performed before and after the NVM write?
  • Do you perform any SPI operation on the volatile memory before the 30ms timer has expired?
  • Can you check the value of register 26 when the NVM write fails.
  • What SPI frequency is used?

Best regards,

Carmine