ESP8266 Community Forum

- Sat Mar 21, 2015 2:35 am #12371 A friend of mine reported the same issue. PIR stays on all time. I thought was RF issue initially but after many tests it appears to be power rail. Most ESP modules does not come with a decent bypass cap on the power rail. During RF activity it can cause 100mv spikes at 100ms interval. I put ESP-01 onto its own regulator with a 22uF tantalum cap and it works fine now.

My ESP8266 dev board https://www.tindie.com/products/Ba0sh1/ ... d-adapter/

- Sat Mar 21, 2015 11:49 am #12387 Are you saying that you used a separate power source for the ESP than what powers the PIR?

i tried a lot of different capacitor things but nothing I tried cured the interference.
I'm planning on making the PIR units battery powered, so the work-around of leaving the radio off while waiting for PIR interrupt probably gives me an advantage in battery life.

I've tried to experiment to see how to wake up the ESP from deep sleep with the PIR sensor but so far haven't figured out anything that works.

- Sat Mar 21, 2015 11:34 pm #12413 I thought I had a bunch of bad PIRs. Thanks for this info.

- Sun Mar 22, 2015 9:42 pm #12452 The only thing that will work as a lot of very careful shielding , including on the window of the sensor itself, and top notch pcb layout design using every trick in the book.
Don't ask me how i know..