gswan
Well-known member
Got one of these that powers up for a second (blue led comes on) and then the fuse pops.
Opened it up, looks like a basic off-line SMPS (uses the TOP245Y device) and the class D switching amplifier (TDA8932B in BTL). There's some simple input circuitry for the line signals as well.
Initialliy looked for a PSU crowbar, but there does not appear to be one. So next guess is that the amplifier gets unmuted maybe after a second and the output drivers are shorting. The speaker appears OK.
Anyhow, just curious to know if anyone has a circuit or has traced this before I go in and do the same (no circuits could be found elsewhere and B don't release circuits into the wild).
cheers,
Geoff
Opened it up, looks like a basic off-line SMPS (uses the TOP245Y device) and the class D switching amplifier (TDA8932B in BTL). There's some simple input circuitry for the line signals as well.
Initialliy looked for a PSU crowbar, but there does not appear to be one. So next guess is that the amplifier gets unmuted maybe after a second and the output drivers are shorting. The speaker appears OK.
Anyhow, just curious to know if anyone has a circuit or has traced this before I go in and do the same (no circuits could be found elsewhere and B don't release circuits into the wild).
cheers,
Geoff