DRV8871: DRV8871

Hello!

Can you please add more details?  I am not understanding the issue.  Scope captures would help.  Also, can you share your schematic? 

Regards,

Ryan

hi,

I am using the next EVB:

https://www.adafruit.com/product/3190?gclid=CjwKCAjw6dmSBhBkEiwA_W-EoGmWCsf1SA0BHdxR9lABQiQVr3zd3RJpBFqV404DGugHS6XFkkjtHxoCMOYQAvD_BwE

this EVB connected STM32 on one side and to motor on the other side. sometimes my MCU is ruined.

I tried to do some test to find it can be, in one of them I was disconnected the EVB from all my design, connect probe to pin "IN1" and power the supply on.

my scope shown this signal on pin "IN1"! this is not make sense and i ask if you have any idea.

BR,

Itzik

Itzik,

So, you just connect power and GND to EVB and you see approximately 4.64V on the input?  What is the voltage of the power connected?  Is this a DC voltage?  I see a pulse on the scope, but did you apply power on the rising edge and remove power on the falling edge?

It appears the device is somehow damaged.  I would not expect this at all since inputs are internally pulled down to GND.  Do you have another board to test?

Regards,

Ryan

hi,

yes, power to "VM" and GND to "GND" only and yes 4.64V. I had sample with ~7.6V:

the voltage of the power is 24VDC and there is no power on the rising/falling adge.

the device is new (after test and switch the old one), still maybe damaged, but even though, why it is happened?

BR,

Itzik

Itzik,

When you apply power, are you "hot plugging" the EVM?  This means you turn on power supply and then connect to EVB.

It is better to connect wires to board and then turn on power supply.  A fast ramp on power supply could cause some damage to ESD cells on device.  If you have a new device, you could try this procedure.

Regards,

Ryan