NUCLEO L073RZ board heating up

[Hemanth V]

Posted on February 06, 2018 at 18:47

I am seeing a problem with couple of my Nucleo L073RZ REV C boards which starts to heat up when powered using VIN i.e 12V supply. The boards are working fine, but I can feel the temperature increase if I touch the backside of R29/R30 resistors.

If the board is powered through USB or even if USB cable is connected (powered using VIN) I don't see the temperature rise. Anyone know the reason for the same.

Thanks

Hemanth

[AvaTar]

Posted on February 07, 2018 at 08:11

I would try reducing the input voltage, say, to 9V or less.

Most cheap 'wall warts' have a considerably higher output voltage at low load conditions.

[AvaTar]

Posted on February 07, 2018 at 08:18

If you didn't realize it - the voltage regulator at Vin (LD1117S50) is of the linear type.

It converts (Vin - 5.0V) * Iout into heat.