How much current will I get?

[szzuk]

I am not getting enough current from the OPA453 opamp I just put on a veroboard, the datasheet says I can increase the current output by putting another OPA453 in parallel with the original in a master slave/buffer setup. But how much current would I get?

The OPA453 has a current of 50mA, but is using the buffer setup going to just double the output to 100mA? Or will I get more.

Regards,

Szzuk.

 

[alec_t]

You will just double the output.

 

[szzuk]

Thanks, it won't be enough so I'll try another chip or add a transistor.

 

[Blueteeth]

As you said you could add a transistor, but it depends on your circuit, and if you can tolerate any errors a transistor output stage may introduce. Many audiophiles who make 'high quality headphone amps', have been known to parallel/stack several opamps (most I've seen is 9....) for reduced output impedance. Can be an expensive way of doing things, and may not always provide the best results. But two opamps seems to be faily common.

 

[szzuk]

I'm not exactly sure how much current I need, I will need to measure that today. 50mA didn't look close, so I'd need more than two, putting 9 in parallel at £5 ($7) each would be a bit pricey and complicated. I'd prefer to avoid using a transistor for the reason you mention so I'll probably end up looking for another chip.

 

[Nigel Goodwin]

Perhaps you might mention what you're trying to do? - you may well be going about it the wrong way?.