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Re: Low Power Battery Powered Surveillance Application

PostPosted: Wed Jul 28, 2021 9:22 pm
by acronce
RainerOchs wrote:
kolalde wrote:- the 1M resistor slowly drains the 220uF cap that was charged when HCT pins1&2 were pulled to ground. Seems to take roughly 4.5 minutes.

My design uses a 100nF (not uF) with a 4M7 Resistor what makes a time constant of about half a second. This is enough for the ESP to reset.

What a great project RainerOchs! It's very close to what I'm looking for.

Of course I'm 5 years late to the party. Hopefully it's not too late for a noob like me to ask a question.

You mentioned a 100nF cap and 4M7 resistor above. But your Eagle files indicate that C1 is a 220uF cap and R2 is a 1M resistor, as indicated by kolalde.

I'm trying to pull together the parts for a prototype. Sounds like somewhere along the line you changed the values of the cap and corresponding resistor in the Eagle file to shorten the time for the reset. Is that correct?

After shopping around 100nF 1206 caps are much more affordable than 220uF caps at that form factor. I just want to make sure that I'm getting the right parts that work well for this project.

Apologies in advance for being a noob. I'm a software guy who's trying to branch out into hardware.