[till]

I have built a direct-coupled Szekeres, no gain stage. The PS gives 24 V DC, this is split by a TLE2426, which is followed by a BUF634 (DIP version). According to the datasheet, the BUF634 can give a 250 mA output surrent. Is that sufficient for the Szekeres? I'm asking because after running peacefully for some time, the amp seems to have fried a BUF634; the voltage was no more split evenly (-16 V and +8 V instead of +12/-12) until I swapped in a spare buffer. Judging by how hot it gets, it seems to draw a whole lot of current

So, should I consider to build something different (or use stacked buffers) to split the voltage?

 

[guzzler]

build a proper dual supply using LM317/LM337, don't bother with virtual ground, make it a real ground

the Szekeres is a very ineffecient circuit, and most implementations use 250mA-300mA per channel on the supply (not to ground). Compare that to 100mA for a PPA with 3 channels, and you see my point.

edit: +/- 12V is far too much for it as well, go with +/- 7.5V either side at most, otherwise you could heat your house with it!

g

 

[Glassman]

you must have something wrong, check your amp for any errors, there might be some low impedance contact with the virtual ground and one of the rails.. the current draw must be well under 100mA (from the ground point)

 

[tangent]

Quote:

BUF634 (DIP version)...can give a 250 mA output surrent

Nope, sorry. The TO-220 and DDPAK ones can provide that much, but not the DIP and SO packages. Also, with that kind of output current, you really should be adding a heat sink. You probably overheated the chip.

 

[till]

Thanks, guys

Looks like I'll order some parts for a proper power supply... and I'll lower the voltage, too