Op-Amp buffer output impedance check/help

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juz_ad

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I'm hoping someone can take a quick look at this and double-check my assumptions.



Standard op-amp buffer as output. Input is from 'in-circuit', output is to the outside world.

Is the impedance of the jack output still 1K even though there is an LED driver also hanging off the same op-amp output?

Any real reason why not to do this under 'normal' use?

<Edit 1> Input signals are 0V or +10V only - it's an output for a logic device. No negative or AC signals.

Thanks!

J
 
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Even if you assume worse case that the base of the bjt is at ac ground, that would still leave you with a 1k in parallel with a 100k, so yea it should still be approx 1k. if this was an analog signal id say yes there is a reason, noise. but for digital not really, except the extra current from the led circuit. only other reasons i can think of not to do this for reg operation would be costs and space savings.
-Pb
 

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