I have the following circuit.
It is intended that when the USB cable is plugged in, and powered, that it powers the CH340G chip, and disables the Bluetooth module.
Ignore JP2, its removed, that's just there so I can power the Arduino from USB, rather than the external supply.
The issue is, that when the Arduino is powered externally, the CPU_RX and CPU_TX pins are pulled up to 5volts, which goes to the CH340G, and bleeds through to the VCC pin, which pulls the USB_5V high, and turns the Bluetooth off.
I currently have it assembled exactly as per the diagram, but R13 and R54 really should be more like 22ohm, not 1k. As it is, the USB_5V is still pulled up to about 3volts, which isn't enough to properly enable the Bluetooth module, but this really isn't a viable solution.
Other than just sticking a diode on the input of the CH340G, which I won't be able to easily do, are there any other options?
Also, before I go any further, is there anything else wrong with my design?
Thanks for any input!