TPS51125 on C650

[salawayon]

I'm having problem with the 5vdc output of tps51125. Pin20, 21, 23 and 24 had no measurable voltage in it. At pin22 it had 5vdc. Tried already replacing tps51125.

Any info?

Thanks.

[whaldsz]

Re: TPS51125 on C650

Measure the following pins - 1,3,6,8,13,17 and post back results.

[salawayon]

Re: TPS51125 on C650

Sorry, the unit been pulled out already. I've encountered this problem in acer and macbook. But at macbook it still powered up and the only problem is it doesn't have lcd backlight. I really wanna know how this chip works...

Thanks.

[Francisco.s]

Re: TPS51125 on C650

I really wanna know how this chip works...

The best way is reading out the data-sheet.

[spidey]

Re: TPS51125 on C650

on mac book 5v appears after pressing power button, for backlight you need to have 3 main signals vin, on/off and dim. if you cant trace the problem just check which signal doesnt exists and separete that pin from mobo and apply the signal which you'll find somewhere on the mobo by a resistor and a wire.