What is the standard power consumption when RF disabled ? Can it be reduced ?

[Altero]

Hello,
I am using a ESP32-S2-WROOM (based off ESP32-S2) and I am measuring a 60 mA current drained by the ESP32-S2-WROOM when the module is awake running with RF disabled (Wifi not initialized). Basically that is what the module consumes when I am doing very basic stuff, such as reading GPIO, or even just sitting there waiting and doing nothing in a loop.

So where is this 60 mA going, is it all to the CPU ? Can it be reduced somehow ?

The datasheets state different values in various states:
- Active (RF working) : between 68 and 190 mA average
- Modem-sleep : between 14 and 22 mA
- Light-sleep : 550 uA
- Deep sleep : 20 to 235 uA depending on config

Now I'm not sure what state the device is in when RF is disabled. I would like to achieve ranges in the Modem-sleep current consumption if possible, but its not clear in which condition we can get into this state or if this is a state where the module is running or in pause.

Any advice ?

[ESP_Jan]

Hi Altero,

Take a look at this power_save example.

The consumption seems quite high with the RF disabled. Try disabling wifi in menuconfig.

How are you measuring the consumption?
Are you measuring the power to the chip or the entire board?

You can further reduce power consumption by utilizing light sleep and deep sleep.

Feel free to post any follow-up questions.

[Altero]

Hello,
thanks for taking the time to reply. I just found the issue, while I was preparing a reply.

IO26 of the ESP module is connected to an external IC which is driving the pin, but the ESP32-S2-WROOM uses this pin to as SPI flash CS, which comes in conflict. Result is there is an important current flow between the pins IO26 pin and the external IC pin. Configuring the IO26 pin as input reduced the power consumption to 26 mA. I will double check all the pins to make sure there is no conflicts on next PCB revision.

So the ESP module power when not using RF is easily below 30 mA.

Thanks again