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ESP-01 3.7V Battery Voltage Dropping Need help!

PostPosted: Thu Jan 05, 2023 3:15 am
by aphlox
Hello,

I am trying to run a ESP-01 with a PIR sensor powered by an 18650 3.7 V battery

I have used:
  • HT7133-1 LDO regulator 3.3V
  • 1000uF 10V Capasitor
  • 100nF Ceramic Capasitor
As in the sketch below.

When the switch is off voltage is stable at 3.3V but as soon as I turn on the ESP-01 voltage starts to drop gradually to around 1.5 volts and ESP switches off. I am not experienced I could use any help thanks in advance.

Image

Re: ESP-01 3.7V Battery Voltage Dropping Need help!

PostPosted: Thu Jan 05, 2023 7:45 pm
by davydnorris
What PIR sensor are you using? I suspect that is the culprit.

Also where is your negative/GND power supply connection? Nothing seems to be going to the negative/GND power rails from the LDO

Re: ESP-01 3.7V Battery Voltage Dropping Need help!

PostPosted: Sun Jan 08, 2023 1:06 am
by aphlox
davydnorris wrote:What PIR sensor are you using? I suspect that is the culprit.

Also where is your negative/GND power supply connection? Nothing seems to be going to the negative/GND power rails from the LDO


I am using HC-SR501. But even if I disconnect the PIR sensor ESP-01's voltage still drops.

Ground connection is there I forgot to draw it I updated the skecth.

Re: ESP-01 3.7V Battery Voltage Dropping Need help!

PostPosted: Sun Jan 08, 2023 5:17 pm
by davydnorris
Does the ESP-01 board have a LED? Is it on when you turn on the switch?

Would be really good to see the current draw - can you wire a multimeter into the circuit?

Also what is your sketch doing? If you have the wifi turned on then the current draw is quite high