hi there,

does anyone have an idea for a low noise audio amplifier with an output of about 1watt using opamps. the output will be connected to a pair of headphones and the input to a microcontroller..

ANY ideas would be appreciated!!

A

 

Have a look here:

http://www.national.com/analog/audio

You will find many.

 

Opamps are not power amplifiers. A few opamps can drive 600 ohms headphones (at a power of only 60mW) but cannot drive 32 ohms headphones.

You can add transistors to the output of an opamp to make a little power amplifier to drive low impedance headphones.

1W into headphones will blow your head off! And you will be deafened.

 

Thanks!! I understand that 1W into headphones is toooo much... Will the transistors (darlington pair) on the output of the opamp be sufficient for an amp similar to a class d amp? I read that class d amps are good amps, but what is the difference between classes and what would you suggest for an audio amp? I read that different configurations are categorised in different classes and that noise also has an influence on the class the amp is categorised in..

 

Hello,

Here is a page from the EDUCYPEDIA on amplifier classes.
http://www.educypedia.be/electronics/amplifierclasses.htm

Here is also another page with some audio amplifier circuits from the EDUCYPEDIA.
http://www.educypedia.be/electronics/circuitsamplifiers.htm

Greetings,
Bertus

 

Is a circuit with a dual low noise op amp (NE5532) sufficent for your application??

Try
http://www.redcircuits.com/Page119.htm

 

any circuit able to to give an output of more or less 100mW would be perfect, as long as it has a gain of about 100 - 200 and almost non existing noise...

Thanks!!

 

thanks for the circuits!! these really helped a lot!!!

regards