Need hele with building a audio amplifier using LM1875T


Hi all.

I’ve decided to take on a small project into building a 2.1ch audio amplifier.

I’m using some LM1875T audio IC’s (this one:, and the datasheet see: and I want to know how to build a bridge amp out of them.

Do you just connect the outputs + and - together and that’s it? Is it that simple?

I read through some of the datasheet and saw that it is applicable for a bridge amp but I can’t find to many details on how exactly to bridge it. Just for reference my plans are to bring the L/R signals into a summing amp and then run that into my LM1875 with a LPF of 300hz or so.

I run my circuit’s on Multisim and I get pretty good results in a AC analysis through my summing amp but I don’t know what exactly goes on when you bridge. I’ll keep checking back and if I don’t get much info I’ll see about using a different IC to get more power to my sub. I just like to stay around with the LM1875 because I’m somewhat familiar with the chip and their pretty convenient to design around.:joy:

Best regards!


The Electronics StackExchange forum might be a more appropriate place to post this question. (link) :slight_smile:


Fine, thanks bro.


No worries. My impression is that most of the folks here aren’t working at the level of the question you’re asking. :slight_smile: