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Power down during deep sleep mode
Posted: Wed May 15, 2019 4:37 pm
by migbur
Hi
I'm working in a project that send data to cloud each hour with ESP32.
I'm using "esp_deep_sleep_start();"
If I power down "With a physical switch", the module during deep sleep mode. when I power up the module did not startup, just is possible to start again with a manual reset.
Do you know how to set the deep sleep in order to avoid this situation?
Regards
Re: Power down during deep sleep mode
Posted: Thu May 16, 2019 1:36 am
by ESP_Sprite
Possibly you have a capacitor in your design that is normally used for decoupling, but also retains some power when you use a switch to power off the device; as the ESP32 in deep sleep mode only uses a tiny amount of power, it will 'stay alive' off of that. If that's the case, there's no working around this in software, as to the ESP32, the situation is indistinguishable from it being normally powered. Perhaps you can use an SPDT switch as an on/off switch to connect Vcc and ground when the device is powered off?
Re: Power down during deep sleep mode
Posted: Thu May 16, 2019 8:15 am
by migbur
Hi
Thanks for you answer
And yes i'm using a big capacitor to avoid "Brownout detector", I got an GSM module connected with ESP32
I'm using two batteries 18650 2200ma, with a DC DC converter to increase the voltage to 5.2V connected to ESP32 VCC pin
ESP32 board used are MH ET LIVE ESP32 minikit arduino IDE
I'm using SPDT switch to power on/off all circuits.
When I power off the switch the indicator power LED lit for a time decreasing slowly but if I power off in normal operation the power LED stop to lit immediately, curious
At the moment i'm using a big delay, is not an other kind of sleep option or parameter like "ESP_PD_OPTION_ON" to avoid this behavior or other alternative like left the secondary processor running.
I think if I power off on deep sleep mode the ESP32 are unable to reboot and stay on unknown mode, or is possible that they stay in sleep mode after power on and for this reason I can't see any activity?.
Re: Power down during deep sleep mode
Posted: Thu May 16, 2019 11:13 am
by ESP_Sprite
My guess would be the 2nd option, that the device indeed stays in deep sleep mode. Can you see anything on the serial port when the power is turned back on?
Re: Power down during deep sleep mode
Posted: Thu May 16, 2019 11:23 am
by migbur
No activity in Serial port
I tested configuring the sleep mode just 3 min, power OFF on sleep time and power ON, wait 3 minute, but not restart, can be recovered just if I do a manual restart or load again the configuration.
can someone with ESP32 can tried this test?