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I have the same problem. In my case, on ESP8266-01S I use Tx, Rx as input, GPIO0, GPIO2 as output to control 02 DYI SSR relay together with 02 TTTP223 touch module. If Tx would be connected to TX pin, ESP8266-01S wont boot, if i remove the one connected to TX then it boot up normal, then I plug the TTTP223 in again, the touch button work. After sometimes, I ...


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Using 5V as a supply to power a relay coils that are rated for 3V is not valid and it might damage the module.


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R2 is necessary to make sure that the mosfet M1 is in cutoff even if nothing is driving the GPIO12 line. This is important during power-up, for example, at which time the MCU in this system may not be driving GPIO12. If this resistor were absent, the mosfet might turn on during startup and engage the relay erroneously. R1 is not necessary because M1 is a FET....


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Removing power from the sensors is the best way to reduce power consumption when you don't need them. You can do a low-side switch because your sensors don't use a lot of current so that ground will be so close to real ground that it won't matter. The pins of the sensors however may be at VCC level so you have to watch where they connect, for example the I2C ...


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HV board #1 the copper pour should NOT get close to the high voltage traces. You need a good distance between high voltage and low voltage, so get rid of that pour. You can keep it on the low voltage part of the board, but it should not get close to the high voltage pads. The bottom left part looks good, nice distance between high voltage and ground plane. #...


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It's hard to find useful layout documentation to your ESP8266-12E; but I bet the antenna mustn't be placed above signals, and it's likely it shouldn't be placed above any copper at all. Espressif themselves have reference designs where the antenna should be sticking out from the rest of the board: It's a good idea to route signals on the top layer, sure, ...


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If there is no load at all on the 3V3 regulator, it has no minimum required load so it won't output 3V3. When there is no ESP connected, there is nothing connected on HC595 input pins, so they are floating. The input impedance is so high that taking multimeter probes nearby will cause the HC595 to see activity on input pins and it will randomly load in a ...


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Throw away that pcb before it kills you and burns down your house - I’m not joking. As others have observed, the clearance between tracks carrying mains voltages and low voltage tracks is nowhere near safe. Have your mains wiring down one end of the pcb well away from the low voltage circuit. What current do you expect to switch with the relays? What voltage?...


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