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Joachim Wunder Joachim Wunder is offline
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Default PCB of garage door opener failed: Which PIC is this?

On Fri, 09 Feb 2007 00:32:28 GMT, "Arfa Daily"
wrote:


"Homer J Simpson" wrote in message
news:01Pyh.38172$Fd.27523@edtnps90...

"Joachim Wunder" wrote in message
...

Unfortunately not. I already phoned them up today. And, no, they are
not the manufacturer of this Liftboy SMD 3200. Any other ideas are
highly appreciated.


Any other info on the labels? Country of origin?


Judging by the amount of heat that has been pouring off that regulator, and
discolouring the board above, the first thing that I would be doing is
removing that chip that says " VOH " on it from its socket and cleaning the
pins. What exactly is the board doing wrong ? Assuming that device is a PIC,
in general, they are very reliable.

Arfa


Well, ok, cleaning the 16-pin ICīs pins will be easy, and Iīll do so,
of course. Well, from my first investigations the 40-pin PIC is very
likely to be an Intel 8748 or 8749. Question now is what current PIC
is still compatible to this old-fashioned one.

The whole board should control the 220V~ motor of the garage door
opener, but nothing happens no more. The board behaves like dead.
Reason might be a 25W bulb which blew off just before the board didnīt
show any reactions no more. The 25W bulb is connected in parallel to
the PCBīs power supply.