STM32L073VBT6 COST 100mA，Help

[ren yong]

Posted on March 14, 2018 at 08:09

My product with stm32l073vbt6 ran 1 week or longger,the mcu was broken.

All io and peripheral on broken mcu can run as normal,But the power consumption up to 100mA not 100uA!

I have removed all other part but mcu and supply 3.3V my own，the state  not changeï¼�

How can a mcu cost 100mA without any other chip when all function ok？

[Bogdan Golab]

Posted on March 14, 2018 at 09:31

Really bad news (if the problem does not come from broken external circuitry) as this may require the PCB design changes...

And of course some design review...

[ren yong]

Posted on March 14, 2018 at 09:32

How to explain

all the io work correct?

[Bogdan Golab]

Posted on March 14, 2018 at 09:34

Do you mean these kind of requirements to review:

http://www.st.com/content/ccc/resource/technical/document/application_note/a2/9c/07/d9/2a/b2/47/dc/CD00004479.pdf/files/CD00004479.pdf/jcr:content/translations/en.CD00004479.pdf

 

Just wanted to learn something from this post;)

[ren yong]

Posted on March 14, 2018 at 09:34

The VDD USB not flow the datasheet. I float the USB io and VDD USB cause I have not use usb .

[ren yong]

Posted on March 14, 2018 at 09:58

Thanks for your help�?It is a long way to find the reason why and fix how!

[AvaTar]

Posted on March 14, 2018 at 10:00

Not explicitely, I am no hardware designer.

However, this document look useful in this regards.

But experience and logic, applied to the O.P.'s facts, suggest one of those (power or IO).

[Bogdan Golab]

Posted on March 14, 2018 at 10:05

Yes, I noticed that I was wrong (heating vs capacitors not connected to IO pins make no sens)

[T J]

Posted on March 15, 2018 at 01:10

the circuit looks ok, you blew it up...

there is no signs of 6V 12V in your circuit..

what did you do ?

sometimes a static charge blows the chip whilst it is being handled before mounting..

this may be your issue.

do you use Antistatic precautions ?

[henry.dick]

Posted on March 15, 2018 at 03:05

'

How can a mcu cost 100mA without any other chip when all function ok？'

When it is abused, damaged, or otherwise mis configured.

[ren yong]

Posted on March 15, 2018 at 09:48

The circuit with diff voltage all with mos or res as below.