ESP32: Schematic to blink LED during deep sleep

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My goal is to have a circuit that allows me to disable the LED, enable the LED at 100% and to blink that LED. This should all be possible to happen while the ESP is sleeping.

As far as I know, I cannot make it blink using software while it is in deep sleep. Hence the need of an external hardware network.

I was reading about the 555 IC. It should be possible to keep it in reset state by driving the Reset pin by the ESP to disable the blinking effect. On the other hand, I want the ESP to be able to keep it on at all times. As the ESP works on 3v3 and the 555 on 5V, I cannot drive the LED directly as well with the ESP by connecting the out pin of the 555 with the ESP gpio.

What can I do to achieve this?

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if you could find a way for not needing the "always on" state (may be consider 2 LEDs instead of one), you could buy a LED that blinks by itself (1 Hz often) when powered. This way you don't need a 555

(look for "1Hz auto flashing LEDs" - they come in various colors - here is a first google hit https://lighthouseleds.com/led-component-lighting/animated-leds-flashing-blinking/3mm-led-flashing-round-top.html)

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You could make an OR-port with two diodes; I usually use a BAT54C for this purpose. The OR port could drive a suitable MOSFET or NPN transistor that switches the LED, the LED can then be powered (with an appropriate resistor or constant current source) with whatever voltage you desire. The ESP could drive one input of the OR port and the 555 circuit the other. Since it's a logic OR, the LED will be on if either or both the inputs are high. This seems to fit your requirement.

The main thing you'd have to work out is whether the power savings justify the added complexity of the circuit. I've not looked deeply into the various ESP32 power savings modes, but I recall that it doesn't consume all that much power if you turn all RF-related functionality off. Perhaps you can shave off a little more, still, while keeping GPIO functionality available. This may turn out to be more flexible and quite as effective as some additional hardware.

I'd start by determining a power budget and see how much you have to spare, and then choose whatever option is the simplest while remaining within that budget.

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Thank you all. It made me indeed realize not to over complicate my circuit.
I ended up having a look at the ESP32 ULP for blinking the LED during CPU sleep.

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