820-00165 Keeps blowing backlight enable resistors

[bjf]

Has anyone had this issue where R7715 and R7731 keep blowing? The resistance to ground is good on all the pads. I replaced U7701. No change. Not sure why, but it looks like there's a surge coming into R7731. Or something is happening on the other end through R7715 and U7701. Board is otherwise functional.

 

[dukefawks]

With the voltages present on the board it is 100% impossible to blow these resistors. Why do you think they are dead?
You could do some basic math and calculate wattage with the voltage present and resistance. P=V^2/R. 0201 resistor is typically 0.05W.

 

[bjf]

I love a good riddle, but I can't think of anything else that could be happening besides my initial two guesses. I'm measuring no shorts.

 

[dukefawks]

Voltage on BKL_EN? Again it is impossible to kill them!