Power Consumption in Deep Sleep

[fleckingerre]

Hello!

I'm using the ESP32-DevKitC from Espressif. Currently the board draws around 10mA while in deep sleep. Is there any way to lower the power consumption even more? Ideally the power consumption should drop below 1mA while in deep sleep.

I also couldn't find any way to power down the CP2102N via code. Plus, neither of the available PCB Documents from Espressif seem to match the board that AZ-Delivery sells: https://www.az-delivery.de/products/esp ... oard?ls=en

Many Greetings!
Remo

[fleckingerre]

After desoldering the CP2102N the board consumes around 3mA power. I guess after desoldering the ESP32 on another board it can be used to program the board without the CP2102N. If someone finds a better solution I'm all ears.

Many Greetings!
Remo

[ESP_Sprite]

You possibly also want to replace the LDO, the default one is most likely an AMS1117, which is cheap and cheerful but has a somewhat high quiescent power use.

[fleckingerre]

Yes, thank you!

[fleckingerre]

With the masses of LDOs available I'm having trouble finding one that matches all criteria:
has to be pin compatible to the AMS1117
must not have a minimum current requirement
must have very low quiescent current draw
should have very low dropout voltage (1 cell lithium battery operation -> 4.2V to whatever the LDO supports)
available in online shops

Any suggestions?

I get the feeling the DevKitC is somewhat poorly designed and doesn't facilitate the possibilities of the ESP32 very well. The designers certainly didn't have battery operation in mind.

[fleckingerre]

This is a serious monologue here and it needs a closing statement: After switching the LDO the power consumption dropped to around 0.14mA. I'm very happy with that.

[martinayotte]

After switching the LDO the power consumption dropped to around 0.14mA.

Which kind of new LDO have you chosen ?

[fleckingerre]

DII
AP7361C-33ER-13
https://www.digikey.at/product-detail/d ... ND/8545922

[EDsteve]

After desoldering the CP2102N the board consumes around 3mA power. I guess after desoldering the ESP32 on another board it can be used to program the board without the CP2102N. If someone finds a better solution I'm all ears.

Many Greetings!
Remo

Hi,
i am dealing with the same (worse) problem. Deep Sleep power consumption is 12mA on the naked dev-board (with the LED removed). I even run the board directly from 3,3V to the 3,3V pin. So i don't even use the LDO.
Any idea why it uses 12mA? I used the deep sleep example code for my tests without anything connected to the board.

When i cut off the CP2102N from the 3,3V line then the ESP won't work any more as expected. Maybe it is the CP2102N. But that chip should consume not more than 3mA. How did you desolder the CP2102N? Heatgun?
EDIT: I cut it off on the wrong spot. If the CP2102N doesn't get 3,3V. Then the power consumption reduces 10mA. At least on my board.

I am using the dev board in the attachment. If i run the ESP directly from 3,3V. Is there a way to cut off all the parts which consume power?
It's confusing. No LDO, No LED but still 12mA in deep sleep. Doesn't make sense to me. Hmm Any idea?

[Tradiot]

I have exactly same situation with esp32 wroom dev 38 board. 10ma deepsleep. Not made any effort yet to improve, but will.

However I also have a esp32 ’sparkfun Thing’ which is specially designed to have jumpers cut on the back of the pcb . Deep sleep is less than 50ua ( no typo) repeat 50 ua . Amazing board .