ESP32 Forum

Hi ESP32 Forum,

I hope you can help me understand why my setup is eating my battery within 24 hours even though it is in Deep Sleep mode.

Helpful friends on the Blynk Forum (see my post) has helped a lot - but I still does not have my problem solved.




It works as intended; goes on Wifi...posts to Blank...then goes to DeepSleep....and it wakes via the Reed and does it all over again.

Why does this setup drain my battery?

Any idea how much current it pulls in deep sleep? If any, your board uses an AMS1117 regulator - these are pretty bad for deep sleep power consumption, as they use a fair few mA by themselves. I'd advise you do desolder that and use a different one, but you may be better off by looking for a devboard that has a 'native' connector for a LiIon cell - the people who build those usually think about deep sleep.

Hi ESP_Sprite,

this is very interesting what you mentioned. It is indeed using an AMS1117 regulator. My USB Volt/Ampere Meter measure Amps - and is stating 0,02A / 20mA in deep sleep. So there is definitely something there.

Using boards with included battery connector makes sense. Found these 2, and they are ordered now: SparkFun ESP32 THING and a FireBeetle ESP32. I hope these can help me save power.

I checked my other ESP32+ESP8266 board and they almost all use the AMS1117 regulator. I think I can manage to remove the component. Can you answer this - If I remove the AMS1117, I have no choice but to replace it, right? Googleing I found that the HT7333 could be a good replacement. Do you know this component, and would you agree?

On that not - this video is very inspiring. If I were to build a setup he uses, how would you recommend using that instead of the AMS1117? Probably not easy to solder on...?

Thanks again!

You either need to replace the LDO or feed the ESP32 3.3V directly (via the Vin pin, if I recall correctly). Note that you need a power supply or LDO that can deliver at least 500mA - the HT7333 is unsuitable as it can only do 250mA. You could pick something like the HT7833 instead.

Also note that this may not get you down entirely to the 16uA that the ESP32 can do yet - I've heard some things about the USB-to-serial chip also using power, but I don't know what the workaround for that is. I'm sure it's been discussed before on this forum: the search (or Google) may help you there.