Voltage to current converter circuit

[Arouse1973]

The op-amp used was modified to have a low output resistance. As I told you a buffer might be needed if you can't find an op-amp with enough current handling capacity.
Adam

 

[Bharanidharan]

The op-amp used was modified to have a low output resistance. As I told you a buffer might be needed if you can't find an op-amp with enough current handling capacity.
Adam

Does this buffer needs to be at the output of the differential amplifier?

 

[Arouse1973]

The buffer needs to be what is driving the load. Think of inserting it inside the op-amp and the output of the buffer now being the output of the op-amp.
Adam

 

[BobK]

For the third time, why not use an off the shelf audio power amplifier??????

Bob

 

[Bharanidharan]

For the third time, why not use an off the shelf audio power amplifier??????

Bob

Bob,

The LME49722 is an audioop- amplifier, which i used. I did mention that in the previous reply.

Results were similar. it was the one which had much current output. So i picked it.

Will update if I come up with anything.

Bharani

 

[BobK]

If you did, you did not tell us about it here. You mentioned trying two different opamps, one that could deliver a max of 50mA and the other that could deliver a max of 200mA, and then you complain that you cannot get 1A.

Find a Audio Power Amp (which is NOT the same thing as an opamp) that can deliver at least 20W into an 8 Ohm load and it will work.

Here is an example:

http://www.digikey.com/product-detail/en/LM1875T/NOPB/LM1875T/NOPB-ND/1669

Bob

 

[BobK]

Bob,

The LME49722 is an audioop- amplifier, which i used. I did mention that in the previous reply.

Results were similar. it was the one which had much current output. So i picked it.

Will update if I come up with anything.

Bharani

Do you even bother to read data sheets?

IOUT Output Current V= ±15V ±23 mA

That is an OPAMP that can only put out 23mA.

Bob