Dual Op Amp Output Current Comparison

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mediatechnology
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Dual Op Amp Output Current Comparison

Post by mediatechnology »

I decided to do a quick survey of my dual op amp stock to see which op amps have the most output current capability.

I only evaluated one each so there could be quite a bit of sample-to-sample variability. TI for example shows the Isc current of the 5532 to range from 10 mA to 60 mA with a 38 mA typical.

The test circuit was a voltage follower with a 1K inserted in the feedback path to reduce input diode current when the output clips. Rl was 100Ω.
To determine Isc I looked for clipping in the output.

TI 5532 42 mA (old date code)
ON 5532 36 mA
NJM 5532 44 mA
Sig 5532 48 mA (1989)
NJM2114 56 mA
LME49720 48 mA
OPA1612 48 mA
OPA1642 28 mA
NJM4560 60 mA
MC33078 30 mA
NJM2068 52 mA
OPA2134 44 mA
OPA2604 30 mA

Some clipped symmetrically; some uneven. The lowest value was recorded.

The OPA2604's low Isc current was a real surprise as was the NJM2068s respectable 52 mA.
The NJM4560, popular as a headphone amplifer (e.g. the O2), was King Daddy with a 60 mA Isc.
IIRC I read at diyaudio that the OPA1642 had a lower-current output stage to conserve die area for the rather large input FETs.
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