DRV8844: Need help in reviewing the schematic

Badri Ramesh

Part Number: DRV8844

Hello,

I've designed a custom board with the DRV8844. This is the first time i'm using this IC and I need help in reviewing and cross checking the schematic. I can send the schematic image as a private message. Please help me regarding the same. Also i have a few queries,

1) Since the IC is also capable of driving stepper motors, i've assumed it can accept standard PWM inputs on all INx pins from a 3.3V logic micro controller.

2) In case one of the HS or LS mosfets inside the IC burns, how can we know ? and what can we do to perform a smooth cut off ?

3) What else can i add to help in protecting the drive circuitry from spikes generated by solenoid ?

If any other info is required from my side, please feel free.

Thanks,

Badri

over 2 years ago

0 Pablo Armet over 2 years ago

TI__Mastermind 37683 points

Hi Badri,

Please send me the schematic via private message.

Badri Ramesh said:

1) Since the IC is also capable of driving stepper motors, i've assumed it can accept standard PWM inputs on all INx pins from a 3.3V logic micro controller.

You are correct.

Badri Ramesh said:
2) In case one of the HS or LS mosfets inside the IC burns, how can we know ? and what can we do to perform a smooth cut off ?

The driver will protect itself against high temperature or current from damaging the driver. In the case that damage does occur to the FETs or other internal parts of the IC, obviously the IC will stop working and it might be difficult to pinpoint the location of damage (unless it is visible on the IC). Techniques like XRAY images will help to pinpoint damage on the IC. However, swapping the suspected damaged IC with new one will confirm if the IC is damaged internally or not.

Badri Ramesh said:
3) What else can i add to help in protecting the drive circuitry from spikes generated by solenoid ?

This FAQ answers your question: https://e2e.ti.com/support/motor-drivers-group/motor-drivers/f/motor-drivers-forum/1041760/faq-how-to-not-damage-your-motor-drive-system-from-overvoltage

Regards,

Pablo Armet

Motor drivers

Motor drivers forum

DRV8844: Need help in reviewing the schematic