Thinkpads Forum

The battery stopped charging on my X60 (and it's not the battery failure problem). I traced the problem to a blown chip (probably part of the charging circuit) on the underside of the board, but I don't know what kind or manufacturer and model it is to replace it. If anyone knows what it is, please chime in.

X60 planar photo

In the image above, the 6-pin chip is located on the underside of the board right below the big square component labeled L28 (left side of board across from the audio jacks).

Here is a close-up of my burned out chip. It looks like the model number 833A is stamped on top.

My bad chip

Thanks for any help!

My best guess is that it's a MOSFET. That package style appears to be TSOP-6 (Thin Small Outline Package; 6 leads). Popular manufacturers are Siliconix (Vishay), Fairchild, International Rectifier. The code is probably a shorthand as described in this document: http://www.vishay.com/docs/72761/72761.pdf

Here's a list of some TSOP-6 MOSFETS at Vishay: http://www.vishay.com/mosfets/tsop-5-6-package/

I downloaded a couple of the datasheets and checked the marking codes but did not find a match to "83". There appears to be a problem with Vishay's site as it hung numerous times when trying to download the .PDF - you might have better luck.

While it's not very cost effective, the best thing you could probably do is obtain a "parts" motherboard and hope that part is still intact and transfer it to your own board. However, whatever caused the part to blow up in the first place could still be present and you may end up blowing the replacement as well.

Thanks for the info! I too tried to persuade Google to direct me to chip vendor sites, and all of them seem to not want to render PDF datasheet files. I dunno why.

I want to hope that just that chip was growing old in the tooth. Previously, it would charge a battery until very near 100% and then stop charging, blink a fast orange LED, and say the battery failed internally. I seen that battery error many times. But only after completely discharging the battery, I was able to recharge it again, as long as I stopped it from charging to completely full. That was then. Now Power Manager says the battery is charging, but it doesn't and multiple different plugged-in AC adapters don't even get warm. Maybe the chip was too old to handle a full charge?

Anyway, thanks for the help!