Alexandre Aguiar

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10 years, 7 months ago.

KL25Z Smoking?

Well,

When I tried to external power supply the kl25z Board (using the P5_9V_VIN and the Ground on J9), it started smoking.

What's happening?

Thanks,

Aguiar

Can you provide detailed description? What are your power supply characteristics? Even include the exact type. Which part was smoking ? Any of protecting diodes?

Regards,
0xc0170

posted by Martin Kojtal 13 Sep 2013

It happened with my board too. after a long time I found that D2 is open between 1(anode) to 3(cathode), bypassing it I get the frdm working again, but I know this is not safe.

posted by Robson Cardoso dos Santos 14 Sep 2013

2 Answers

Wim Huiskamp
10 years, 7 months ago.

Perhaps the voltage was too high. Note that most (cheap) unregulated powersupplies output much higher voltages than rated when you dont draw much current. The KL25Z does not draw much current so a 9V supply may actually measure 15V under those conditions. Other possibility is that you accidentally used the wrong pins or reversed the polarity of the supply.

Erik -
10 years, 7 months ago.

How much volt did you apply? You didn't switch up ground and power? You have a regular KL25 board? (For example the Wi-Go version is slightly different).

Does it still work from USB? And I guess you didn't happen to see which part exactly was smoking? I once made mine smoke. Accidently shorted GND and VDD, nice column of smoke from the 3.3V regulator, but no permanent damage (well no permanent damage that affects operation).

6,8V. No, the connection was correct. Yes.

It still works from USB, and the smoke was near the D1 and D2

posted by Alexandre Aguiar 13 Sep 2013

Is there any obvious charring around D1 and D2? There is a lot in that general area, including the regulator, U1.

posted by david dicarlo 13 Sep 2013