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To give my ESP32 ethernet I need to have a clock signal on PIN0 but the problem here is that if I start them up at the same time I have a 50/50 chance to go into the bootloader mode (Pin0 high on boot) which is bad. I would need to have a constant way to boot normal everytime I restart the MC - for that some people recommend a delay via a BD5230G which I tried but it kinda failed. After checking why I realised I totally misplaced a transistor that I wanted to use as a fail-safe method to turn on the LAN8720 Chip(PHY)

In picture 1 you see how I "tried" to enable the LAN8720 via a transistor, it didn't work at all so I removed it and bridged 1 and 3 to power the chip on.

enter image description here

In picture 2 you can see how I tried to delay the power on the clock, sadly that didn't work either even without my transistor. enter image description here

For the next version I would like to rearrange the transitor as in picture 3 would that work in combination with the delay but would that work ? enter image description here

ESP_EN/ETH_POWER_EN is on pin 32 which doesnt do anything on boot. For the code I used the example arduino code for the LAN8720 both with and without enable pin but I still have like a 50/50 chance to get into bootloader.

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No, your new schematic will not work.

The transistor, if turned on, will short circuit 3V3 to GND. Most likely the transistor would burn up, or the 3.3V supply would be unable to provide enough current and shut down.

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  • \$\begingroup\$ I thought so.What if I put the vdd on 1(source) ? \$\endgroup\$
    – Daniel Do
    Commented Aug 8, 2021 at 11:15

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