Capacitor on EN helped (ESP32 DEvKitC - WROOM32)

Other Hardware 3rd Party Boards
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I have a ESP32 with 4" TFT and 6 relays on one prototype board that is supplied with a 5V onboard power supply with enough power (25W). Everything is running good, with the exception of fast 220V blackouts. If the 220V AC is more than 30 sec off, the ESP32 will start without any problems.
But when the AC power is only a few seconds off , then the ESP32 was not able to restart . it stopped in a early stage of startup, before the code was executed.

I tried some ways to solve the problem (chaneg Power supply, isolate the ESP32 from other out- and inputs), but at the end a capacitor on the EN input of the ESP32 DEvKitC Board helped. The capacitor is 4.7 or 100uF and connects the EN with ground. That is enough to restart the ESP32 after short AC blackouts. I treid a resistor between EN and GND, that doesn´t worked.
If the EN is connected to ground with a switch during normal operation, it restarts the ESP32.

Do you have any idea, why a capacitor to ground helps in that situation?

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That is contrary to what is suggested in the ESP32 data sheet.
A capacitor on EN would keep the ESP from resetting.

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