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I'm designing this board based on ESP32 which suppose to handle two motor drivers (DRV8874, DRV8840) and a few other modules; a 12V@3A DC adapter seems to suffice powering-up the board according to my calculations. The idea here was to have only one power source to the whole board, even the CP2102A USB_to_UART and ESP32 could both be only powered up via the DC adapter instead of USB port (which a common design in dev-boards is that the 5V on VBUS gate of the MicroUSB goes through a 3.3V voltage-regulator and forms the 3.3V net to eventually supply the VDD on both CP2102A and ESP32 module).

Have I missed anything here? any possible safety issues with the current design? was cutting the power from the MicroUSB's VBUS to the USB_to_UART's VDD and supplying from an external DC source a bad idea? Thanks. ESP32Module PowerManagement CP2102A USB-to-UART

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    \$\begingroup\$ Refer tothe Silicon Labs datasheet for the CP2102 for guidance on powering the device. Note that U2 might get a bit warm. A switching regulator might be required. \$\endgroup\$ – Kartman Mar 9 at 12:35
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    \$\begingroup\$ It's perfectly fine to power everything from 12V. Many designs do it. On first sight, the schematic looks ok. I would check the maximum power consumption of the ESP32. I know that it can have bursts of up to 1A. At 1A, the first voltage regulator generates 9W of heat. That will be too much if bursts are long or frequent. You might want to consider using a buck converter. \$\endgroup\$ – Codo Mar 9 at 12:44
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The ams1117 is a linear regulator. At 12V in and 5V out you are dropping 12 - 5 = 7V at whatever current you are pulling. So at 1 amp you are wasting 7 Watts of power. And without a heatsink you are going to have a bad time.

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