Boss BR600, digital recorder, 2006

The Service Manual identifies it as VEC2302

Gareth.

Ta for that Dual p-ch 3A,30V, buried in the datasheet Marking: BB With the ex-SOIC off the board then traces are consistent with the pinout of that IC with both devices paralleled

Both devices are in series:

S1 -- D1/D2 -- D1/D2 -- S1

This is in parallel with the not fitted D2, so you can just fit a diode in position D2. Maybe a Shottky.

D2 Anode ----------- D2 Cathode

Gareth.

Gareth.

Gareth.

Oops, I left my Space Echo on.

Gareth.

I was going to put an IRF9532 in there as plenty of space for a TO220 but I've no idea what the seriesing is all about so a couple of paralleled shottky SM diodes went in at D2 pads, reassembling/testing next week.

I was going to put an IRF9532 in there as plenty of space for a TO220 but I've no idea what the seriesing is all about so a couple of paralleled shottky SM diodes went in at D2 pads, reassembling/testing next week.

That puzzled me too. I honestly can't see the point of this IC, or understand what it does.

Gareth.

Owner lost the original plug in ps, and tried using another 9V one of the wrong polarity. I changed the connector and polarity and the unit worked for about 10 hours and then bounced back. So something to do with reverse polarity stressing or knocking out one powerFET initially but continued for those 10 hours with the other one or something like that

wrong polarity. I changed the connector and polarity and the unit worked f or about 10 hours and then bounced back. So something to do with reverse po larity stressing or knocking out one powerFET initially but continued for t hose 10 hours with the other one or something like that

This may happen because the new adapter puts more voltage than the original and components like voltage regulators or overvoltage protectors get hotte r and blow. Could it be the original adapter was regulated and this one is not? Thus providing a higher unregulated voltage.

It does not say regulated but I had checked it initially and it was

Talking to an engineer familiar with solar PV controls. He was reminded of the anti-shadowing bypass "diodes" in solar panels. Otherwise a shadow over as little as one cell will kill the output of the whole array, so as little as a good dollop of seagull s*it is all that is required. Say 50 cell panels and each sector of 5 can be bypassed by one of these 2pin powerFET devices built into each panel , output falls in a sector below a trigger level and "diode" kicks in bypassing the 3amps or so of the rest of the array but only dropping .05 volt, so overall array efficiency drop of 1% instead of 90% or whatever with the shadow of a chimney or telephone pole or whatever.

back working again