Electronics > Microcontrollers

Attiny1606 burning out when connected to a drv8251

(1/6) > >>

lavaman:
Hi, I am designing my own locomotive DCC decoder, no need to know what that is. The major problem i am having now is that if i try to use the drv8251 the attiny1606 overheats and then burns out. Even when there is nothing connected to the output, i was just measuring the output voltage with a multimeter. Initially everything was fine, but then, as i said, the mcu burnt out.

lavaman:
https://drive.google.com/file/d/1tMD6DQN1XsESLvD6DEwJkq8qwyXzs5Pj/view

MarkF:
Welcome fellow modeler.  I do HO scale myself with my own custom throttle power controlled by a laptop computer.
   https://www.eevblog.com/forum/chat/model-trains/msg4729595/#msg4729595

I think your problem is going to turn out to be that you're switching the GND to enable the DRV8251.
I'm not familiar with the DRV8251 but suspect the its inputs are floating higher than Attiny Vdd causing
its pins to overload.

lavaman:
I am not sure about that, the drv is using the reference voltage of the attiny, plus those resistors on the inputs should prevent possible overcurrent. Prior to assembling the whole PCB, I tested all the parts individually. First the voltage regulator, then separating the signal. And last i tested the drv. For the test i used the same schematic for the drv as shown in the picture before, but instead of the attiny I was controlling it with arduino nano (vcc 5v). That seemed to work with no problem

uer166:
Check the 3.3V rail when you turn off the DRV. The previous poster is likely correct: you can't switch that IC's GND and not have it back-power all of its' other pins.

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod