When a multi op-amp package(dual, quad opamp, multi channel etc) gives the current output in the datasheet does it specify the current output for EACH op amp seperately, or the total from all of them meaning you divide the output spec by all op amps?

Has anyone seen any circuit design utilizing "multi-channel" op amps to combine the max current output for higher power? If I have a quad opamp package with a supply current of 5mA, can I use them together for 20mA output?

 

It is spec'd per output. Paralleling devices is usually not a great idea because gain and offset of each opamp won't match, and they will fight each other.

 

Poke around for headphone amplifiers, Headwize in particular. Can heads do that alot using back match resistors to absorb offset differences.

There are higher current op-amps around too and also lots of diagrams around to roll your own..

 

Best thing you can do to boost power using two amps is to put your speaker between two outputs (as opposed to grounding one end of the speaker), and have one amp's output inverted with respect to the other amp.

That doubles the voltage across the speaker, which is a 4 times increase in power (all other things being equal, which they never are).

 

Thanks guys that was some good info...maybe I should try and construct my own with bjts from a schematic...

 

Thanks guys that was some good info...maybe I should try and construct my own with bjts from a schematic...

It would probably be better to get an IC to do the job

 

Look here:

http://sound.westhost.com/project109.htm