PCB of garage door opener failed: Which PIC is this?

[Joachim Wunder]

Hi there,

I have a garage door opener named "Liftboy SMD 3200" which was
installed into my garage back in 1990 (in Germany). I couldn´t get any
information about this garage door opener on the net. The motor
control PCB of it just failed this week. I suspect either any capacity
or the voltage regulator to be the culprit. Does anyone know the
manufacturer of the PCB shown under
http://img255.imageshack.us/img255/9023/cimg0094aq6.jpg ?

Unfortunately, the 40-pin PIC´s type isn´t readable under the sticker
at all ´cause its surface seems to have been scratched off under the
sticker by the manufacturer of the PCB. Yagh. Which PIC is it supposed
to be? There is a Quartz which reads "4.000 SUNNY 7624".

Moreover, the same applies to the 16-pin IC: It´s surface seems to
have been treated by the manufacturer of the PCB, i.e. the exact type
has been completely scratched off on purpose as well. Is there any
way to find out which IC it might be?

Please advise.

TIA,
Joachim

 

[Homer J Simpson]

I have a garage door opener named "Liftboy SMD 3200" which was
installed into my garage back in 1990 (in Germany). I couldn´t get any
information about this garage door opener on the net.

http://www.liftboy.co.uk/ ??

 

[Joachim Wunder]

http://www.liftboy.co.uk/ ??

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.

 

[Homer J Simpson]

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?

 

[Arfa Daily]

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

 

[Joachim Wunder]

Any other info on the labels? Country of origin?

No, unfortunately not. Well, on the backside of the PCB is printed
"PRO6101-28" in one corner. That´s all. Well, the garage door opener
was installed into my garage from a small company called "Schiel" from
northern Germany. Well, they said that the manufacturer went bancrupt
a couple of years ago and that they don´t have any spare parts or
information about this product of mine no more.
Well, and the garage door opener "Chamberlain" said to me that
"Liftboy" might have been an US based manufacturer who went bancrupt a
couple of years ago, but they were not sure about it. I called up
Chamberlain not only in Germany but even in Illinois, US.

 

[Joachim Wunder]

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 IC´s pins will be easy, and I´ll 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 didn´t
show any reactions no more. The 25W bulb is connected in parallel to
the PCB´s power supply.

 

[David]

Well, ok, cleaning the 16-pin IC´s pins will be easy, and I´ll 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 didn´t
show any reactions no more. The 25W bulb is connected in parallel to
the PCB´s power supply.

If indeed this is a PIC or some other type of microcontroller, you cannot
just replace it. It has to be programmed with the original code. Good luck
acquiring that since most manufacturers set a bit in the device to prevent
reading the program stored within.

The failure of the 25 watt bulb may be a clue. A bulb can momentarily create
nearly a direct short when it fails. What voltage is this bulb? 220v or
something smaller?

David

 

[Homer J Simpson]

No, unfortunately not. Well, on the backside of the PCB is printed
"PRO6101-28" in one corner. That´s all. Well, the garage door opener
was installed into my garage from a small company called "Schiel" from
northern Germany. Well, they said that the manufacturer went bancrupt
a couple of years ago and that they don´t have any spare parts or
information about this product of mine no more.
Well, and the garage door opener "Chamberlain" said to me that
"Liftboy" might have been an US based manufacturer who went bancrupt a
couple of years ago, but they were not sure about it. I called up
Chamberlain not only in Germany but even in Illinois, US.

At this point I'd buy a whole new one from a reputable company but I know
prices there are higher than here. It'll be a miracle if you can get any
parts for this unless you can track down someone who used to install or
repair them.

 

[Joachim Wunder]

If indeed this is a PIC or some other type of microcontroller, you cannot
just replace it. It has to be programmed with the original code. Good luck
acquiring that since most manufacturers set a bit in the device to prevent
reading the program stored within.

Yes, I am aware of the fact that I would need a PIC programmer and a
new 8748 or 8749 PIC (I´m still not sure which one it really is).
Pretty good question where to still get such a component from, I
know,... is there any equivalent PIC which offers the same pin
assignment and code compatibility of a 8748/8749? I know, even I doubt
that, but I better ask in this group before giving up.

The failure of the 25 watt bulb may be a clue. A bulb can momentarily create
nearly a direct short when it fails. What voltage is this bulb? 220v or
something smaller?

220V AC, as we have in Germany.

David

Joachim

 

[Joachim Wunder]

At this point I'd buy a whole new one from a reputable company but I know
prices there are higher than here. It'll be a miracle if you can get any
parts for this unless you can track down someone who used to install or
repair them.

Yes, I know, chances are low. Tomorrow I´ll try again at the small
German company which installed it back in 1990.

 

[William R. Walsh]

Hi!

I think the large IC looks like an 8031/8051 microcontroller...these are a
very popular, relatively low cost and highly available part. Are you sure
the power supply is working correctly? Perhaps it suffered some damage or
opened a fuse when the bulb blew.

One of these is ROMless, but I don't remember which one. What does the
little pushbutton on the board do?

William

 

[Homer J Simpson]

Yes, I know, chances are low. Tomorrow I´ll try again at the small
German company which installed it back in 1990.

Sometimes they know a guy who knows a guy . . . . .

In a company I worked at, we had 4 injection moulding machines of poor
design and reliability which were made in Austria by a company that went
bankrupt. It was a PITA keeping those suckers going. We had to reinforce
various parts with welded bracing.

The Swiss ones (design styling by Italians) we replaced them with were
expensive but were a joy to work on and would take anything you could dish
out. Watching them mould a 2 litre bowl every 4 seconds was almost
frightening to see.

 

[Joachim Wunder]

Sometimes they know a guy who knows a guy . . . . .

Right. I will give it a last try.

In a company I worked at, we had 4 injection moulding machines of poor
design and reliability which were made in Austria by a company that went
bankrupt. It was a PITA keeping those suckers going. We had to reinforce
various parts with welded bracing.

Hey, could you do me a favour please? What was the name of the company
in Austria? That all rings a bell to me: Company "Schiel" in Germany
still believes, that my garage door opener´s motor control PCB was
made in Austria as well. And when I look at the backside of the PCB,
oh man, the soldering.. like if a 5-year-old child would have done
some work on it. Various parts with welded bracing as well. Ufff. I
will need some real professional soldering work to get all of that
crap corrected anyway.

The Swiss ones (design styling by Italians) we replaced them with were
expensive but were a joy to work on and would take anything you could dish
out. Watching them mould a 2 litre bowl every 4 seconds was almost
frightening to see.

I see.. I am not yet decided, but may do so soon if that hunting for
the manufacturer won´t come to an end soon.

 

[Joachim Wunder]

Hi!

I think the large IC looks like an 8031/8051 microcontroller...these are a
very popular, relatively low cost and highly available part. Are you sure

Well, if I recall it right, then the 8031/8051 microcontroller comes
in plastic package and doesn´t has an EPROM memory like the 8748/8749,
right? So, I tend more for my PIC to be one of 8748/8749, but correct
me if I´m wrong.

the power supply is working correctly? Perhaps it suffered some damage or
opened a fuse when the bulb blew.

No fuse on the whole PCB unfortunately. And, yes, the power supply
still outputs a stable 12V DC.

One of these is ROMless, but I don't remember which one. What does the
little pushbutton on the board do?

The little pushbutton normally helps the installer to testdrive the
garage door open and closed. That´s what I know for sure about this
PCB.

William

Joachim

 

[Homer J Simpson]

Hey, could you do me a favour please? What was the name of the company
in Austria? That all rings a bell to me: Company "Schiel" in Germany
still believes, that my garage door opener´s motor control PCB was
made in Austria as well. And when I look at the backside of the PCB,
oh man, the soldering.. like if a 5-year-old child would have done
some work on it. Various parts with welded bracing as well. Ufff. I
will need some real professional soldering work to get all of that
crap corrected anyway.

It was over 25 years ago. It might pop back into my head but I doubt it.
However these companies had nothing to do with garage door openers.

You could design and build your own replacement, or maybe you could buy and
adapt the parts from a different model.

 

[James Sweet]

Hi there,

I have a garage door opener named "Liftboy SMD 3200" which was
installed into my garage back in 1990 (in Germany). I couldn´t get any
information about this garage door opener on the net. The motor
control PCB of it just failed this week. I suspect either any capacity
or the voltage regulator to be the culprit. Does anyone know the
manufacturer of the PCB shown under
http://img255.imageshack.us/img255/9023/cimg0094aq6.jpg ?

Unfortunately, the 40-pin PIC´s type isn´t readable under the sticker
at all ´cause its surface seems to have been scratched off under the
sticker by the manufacturer of the PCB. Yagh. Which PIC is it supposed
to be? There is a Quartz which reads "4.000 SUNNY 7624".

Moreover, the same applies to the 16-pin IC: It´s surface seems to
have been treated by the manufacturer of the PCB, i.e. the exact type
has been completely scratched off on purpose as well. Is there any
way to find out which IC it might be?

Please advise.

TIA,
Joachim

The IC will have custom firmware on it so you won't be able to replace
it. Chances are unless the regulator has failed in a short circuit and
caused the voltage to rise, the chips are probably fine. Check to see if
the filter capacitor is shorted, I recently repaired an old Volkswagen
ECU that had a shorted electrolytic capacitor filtering the 5V output,
resulting in a dead car.

 

[William R. Walsh]

Hi!

Well, if I recall it right, then the 8031/8051 microcontroller comes
in plastic package and doesn´t has an EPROM memory like the 8748/8749,
right? So, I tend more for my PIC to be one of 8748/8749, but correct
me if I´m wrong.

Hmmm...checking the Intel datasheet for the 803x/805x family shows that some
of them (8051/8052/8751) do have onboard ROM program memory. At least one
UV-eraseable version also exists.

Any packaging could be possible, given how many different companies have
produced these parts over the years. Intel mentions a "CERDIP" package in
their datasheet, which I would take to mean "ceramic DIP".

Another thought just occurred to me...and maybe it occurred to you as well.
Did you pull the chip and check the bottom of it to see if there might be
anything printed there?

William

 

[rebel]

Well, ok, cleaning the 16-pin IC´s pins will be easy, and I´ll 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 didn´t
show any reactions no more. The 25W bulb is connected in parallel to
the PCB´s power supply.

Exactly what markings are on the ?TO220-ish device below the small PCB? If that
is a 3-terminal reg, I'd be checking it out as well.

 

[Arfa Daily]

The IC will have custom firmware on it so you won't be able to replace it.
Chances are unless the regulator has failed in a short circuit and caused
the voltage to rise, the chips are probably fine. Check to see if the
filter capacitor is shorted, I recently repaired an old Volkswagen ECU
that had a shorted electrolytic capacitor filtering the 5V output,
resulting in a dead car.

It seems to me that this is all getting a bit over-complicated. Why would a
simple device like this even need a micro-controller ? Some years back, it
was fairly common practice to put chips like this onto boards, that actually
did nothing. Literally just there for show to make the item look worth the
money that was being charged for it. Anyway, it seems that there is an
obvious transformer, reccies, and a smoothing cap. Is that where you are
measuring the 12v that you mentioned ? The very hot looking TO220 device
next to the smoothing cap is 99% certain a standard 3 pin monolithic
regulator IC, and I would guess that it's almost certainly a 5v one, so do
you measure something like 12v, 0v, 5v on its pins ? If you do, do you have
a 'scope ? Can you measure any clock activity at that crystal ? Beyond that,
without a detailed knowledge of the functionality, and schematics, it's
pretty much impossible to come up with a valid test strategy, that's likely
to result in a repaired board.

Arfa