Timeline for Do I really need the open loop output impedance of an op amp?
Current License: CC BY-SA 3.0
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Jan 6, 2015 at 20:39 | comment | added | thexeno | I've nearly forgot a precisation: the LM324 is not a sink like others, but have a normal common emitter configuration, so ideally should be zero (and not infinite). There is also the protection circuit which introduce a variation and so on.. And since I have an high closed loop feedback gain, that impedance I think could be even smaller. But Murphy's law apply. | |
Jan 6, 2015 at 16:22 | comment | added | thexeno | @olinlathrop I read links and stuff around, and from what I heard and read, what you say seems the best less-exoteric way to consider things. If I assume the curren source model, as you suggest, in what way "everything should work"? When driving cap loads, I always see the Ro value. I think I am missing something. | |
Jan 4, 2015 at 15:03 | comment | added | WhatRoughBeast | Heh. This is a good example of why you should never entirely trust simulations. The model you incorporate into the simulatioin may or may not correspond to the real device, or at least not closely enough for your particular application. Simulations are excellent for some things, but models based on data sheets, with their unspecified qualities, are no substitute for a real device in a real circuit. | |
Jan 4, 2015 at 14:20 | history | answered | Olin Lathrop | CC BY-SA 3.0 |