mustakhim wrote on Mar 9th, 2010, 4:20am:hye guys,
I'm builiding an amplifier circuit using resistors and OPAMP(LM741). I already got everything about it, but I'm also asked to waste as little power as possible. Is there any solution for this. It seems like a very stupid question. I'm new to designing analog circuit.
Thanks in advance for any help.
That's not as stupid as you might think, although it would have been easier if you could atleast choose a 741 clone from another vendor. Is this for a university project or what?
Anyway, as the 741 has a push-pull output stage, the power consumption depends on the load it is driving. Depending on your specification, you should try to use the largest resistors. And maybe the feedback network can be made with capacitors as the active element and some large R to set the bias point in case your amp does not need to cover DC.
However, if power is really very critical and this is not just a university project or so, then you should be able to argue and convince whoever is making you work solely with LM741s to allow other opamps to be used. Otherwise, it would be really stupid, yes!
Vivek