Hello,
I am designing an ESP32-S3 module based board which has some space constraints. So,i have used external circuit with reference to some designs which i found online which has an 10k resistor and an 1uF capacitor. I would like to know if the EN pin circuit has been designed properly. Please kindly check the attached file and let me know about it
EN pin design review for my ESP32-S3 WROOM-1U module board.
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Re: EN pin design review for my ESP32-S3 WROOM-1U module board.
Generally, that RC network is a balance between startup time and power supply behaviour. With that said, the 10K/1uF combo works fine for most cases. I can't check your schematic as it wasn't attached.
Re: EN pin design review for my ESP32-S3 WROOM-1U module board.
Hello, thanks for your response. Please check this image. Is it ok to put 1K resistor for the boot button?
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Re: EN pin design review for my ESP32-S3 WROOM-1U module board.
Sure. Here's how you figure that out. The datasheet says that IO0 has a weak internal pull-up, and that the value of those internal pull-ups generally is 45K. That means with the button pressed, the voltage on IO0 will be defined by the resistor divider comprised of the weak internal pull-up to 3.3V and the external 1K to ground. This means the voltage will be around (3.3V*1K/(1K+45K))=0.07V. This is below the low-level input voltage threshold for a digital pin, which is 0.25*3.3V=0.825V, so it will be successfully detected as a low value.
(Or you just spitball it by saying 1K is a lot less than the 45K, so it'll generally 'override' the 45K.)
(Or you just spitball it by saying 1K is a lot less than the 45K, so it'll generally 'override' the 45K.)
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