I am trying to debug a failing DC-DC module in a LED lighting project I have just built.
The design can be found here https://upverter.com/StephenHamer/73d5e5450f4a34ee/12V-PWM-Controller/
I have populated the board, hooked up a 12V power supply and LED lighting strand. I am able to control the brightness using a PWM signal driven from a BeagleBone. The lighting works well for several hours. Then I turn the lighting off for the night by setting the PWM to 0 duty cycle at 0Hz (using the http://beagleboard.org/Support/BoneScript/analogWrite/ API).
Sometime during the night the 5V module (https://upverter.com/upn/738daca67feacadd/) fails. When I test with a multi-meter I only see 1.2V
I have tested for shorts, verified resistor values, and visually inspected the module and board. I have had this same failure happen two times. Each time with an entirely new board and parts.
How should I go about debugging this issue? I’m not sure what I should be looking for.