Lenovo Yoga 3 11" - help I.D this ic please.

[reddemonic]

motherboard doesnt turn on. this IC is hot!
i cant find any info on this ic... not enough markings.
i dont have schematic .

board is LA-B921P AIZY0

[khaahk]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

Most likely you have short (or too much current used) on +3V alw rail. Check resistance on the coil (which is showing beneath on photo) relative to gnd.

The ic is Syx196bqnc

[reddemonic]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

Noice. Will check when i get home later. Thanks for id the ic.

[reddemonic]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

after taken the ic out and pin 5 cap out. the +3VLP rail line it is still shorted to ground. i inject 1v in to this +3VLP line and "U11" NPCE288NA0DX got hot. so this ic was the culprit afterall.

[alas3376]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

Deeply chec resistors arround,

[reddemonic]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

i am not sure how. even tho i now have the schematic but there is no board view. i dont know what is the correct value on these resistors. the silkscreen on this pcb is rubbish.

[khaahk]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

The NPCE is most likely dead, also it needs to be reprogrammed after change...
Often the result of the ID pin of adapter getting 19V from +

[reddemonic]

Re: Lenovo Yoga 3 11" - help I.D this ic please.

I found that out on youtube as well. You can buy that programmer on ebay but it is expensive. Not sure if is worth for this single job. I do have a good known working board that i can copy the data from.