Current draw from opamp output

[markusw]

Stupid Q:

which parameter do you check in the data sheets do see how much current you can draw from an opamp, e.g. to power a LED in an envelope follower???

Thanks for your answers in advance!

Markus

[Sir H C]

Should have specifications for current sinking and sourcing.  Sourcing would be current out, sinking would be current in.

[Processaurus]

The LM358 (dual) and LM324 (quad) are good for control circuitry like LFOs and driving an LED in effects with a single supply.  They're cheap and power efficient too.  For current sourcing it looks like it can put out 20mA minimum, 40mA typically. 
http://cache.national.com/ds/LM/LM158.pdf

[markusw]

Thanks  for the clarification!

In case of the TI NE5532 http://www-s.ti.com/sc/ds/ne5532.pdf it would be "Output short-circuit current" ??

Markus

[Sir H C]

That gives you the limit that it can source/sink.  Also it tells you that it can drive a 600 ohm load.