GTA02 power death

Dmitry Shalnoff shalnoff at gmail.com
Sun Dec 23 14:38:45 CET 2012


> BTW, the bass rework looks very similar to what i was doing, i wonder
> who did that :) too bad it looks like i didn't warn everyone strong
> enough (though i did put a big fat warning on the rework page) when i
> discovered the shield must be additionally insulated after the rework,
> i apologise for that :/
>

heh, that thing flicked in my head when I solder capacitors, but I just 
give it up and limit the protection with tiny piece of sticky tape. 
Which is obviously was not enough :)

>
> Can you share the technique you used to desolder it?

with hot air soldering station. but actually I fount that temperature is 
not enough (and I was a bit afraid to overheat PCF50633). So eventually 
I pick it out with the pincer helping myself with classic soldering iron.

this is result of procedure
http://www.shalnoff.com/pics/freerunner_desoldered_inductor.JPG

>
> Taking a closer look at the schematics and the PCF50633 datasheet i
> see that this inductor is part of the main step-up/step-down auto
> converter with an output current as big as 1.1A. It works at 1.7MHz
> frequency (the irc log i found appears to be unrelated). As far as i
> can tell that's unrelated to the self-resonance frequency of the
> inductor (that's always much higher for the modern parts). I'd get the
> one with>1.1A rated current, and on 1.7MHz all of those having
> self-resonant frequency of 50MHz should work decently. I do not
> understand much in EE though so probably you'll want some quick advice
> from those who really knows inductive step-up/down converters.

aha... everything is clear. I'll try one and report the result.

> I never removed LCD too, and everything was fine. It's shielded from
> the heat by the PCB itself, and i doubt you could have heated it up
> too much.

it gives the hope :) will see.

>
> Best of luck!
>

thank you again! have a nice weekend and happy Xmass!




More information about the community mailing list