Peak detector maximum curernt draw

[brain-dead]

Hi Everyone,

I have made a clapper peak detector to turn on a relay when it hears a clap. I have an LM324 op amp and the peak detector is connected to the output of one of the amps as follows:



My question is, do I not need a current limiting resistor in between the output of the op amp and the diode? If no then why not? I have seen many circuits like this and none of them seem to have a current limiting resistor. My concern is that if a large capacitor is used, will this not cause a large unlimited current draw as it's charging, thus damaging the op amp after a while? I have built the circuit and it works great I am just abit confused by it all.

Thanks for help in advance

:smile:

 

[crutschow]

The output of the op amp is inherently current limited so the circuit is using that as a limit. For intermittent operation that should cause no harm to the op amp. It's only if it overheated when continuously supplying current to a short that it could be damaged.