Another LM1875 question

[mrskinny]

I would be interested in a copy of the schematic also, if it is still available. E-mail address is- mrskinny@3web.net Thank you!

[li_gangyi]

in ur last schematic (which I saw) on http://www.diyaudio.com/forums/attac...&postid=295126
you forgot the gain setting resistos from the output to the negative input of the opamp...put that in place and I believe it should work...test the opamp section and make sure it's working BEFORE sticking the transistors in...

[Adi_007]

hi, which is the recommended power supply for LM1875 in bridge mode?....is +/-21Vcc enough or is to much......this amplifier will be used with 8ohm speakers

[johnr66]

Originally Posted by Adi_007

hi, which is the recommended power supply for LM1875 in bridge mode?....is +/-21Vcc enough or is to much......this amplifier will be used with 8ohm speakers

I'd go +/- 18 volts or so (under load). Mount the chips direct on the heatsink as well as they'll need to dissipate a lot of heat for that package style. The tab insulator adds thermal resistance. If you must have an isolated heatsink, use a heat spreader that is electrically isolated from the main heat sink. Consider the TDA2050 as it is rated at 5 amp max current.