Would this USB detection circuit work as expected?
pashkatarakashka
Posts: 1
What I am trying to achieve is detect from MCU, whenever FTDI(FT232R) chip is connected to USB(not enumerated, just powered up from USB).
- When ONLY USB is connected, MCU will get his power supply from +5V bus and will detect on (B) pin that USB is connected.
- When ONLY VR will supply power to circuit, then MCU again will get power from +5V bus, but FTDI will ONLY get VCCIO. On middle of voltage divider R10/R11 I expect there will be 0 and MCU will not detect USB connection on (B).
The question is - would it work the way I described or I missed something? My concern is it ok to hook up only VCCIO to FTDI? Would it damage or lead to unknown behavior?
- When ONLY USB is connected, MCU will get his power supply from +5V bus and will detect on (B) pin that USB is connected.
- When ONLY VR will supply power to circuit, then MCU again will get power from +5V bus, but FTDI will ONLY get VCCIO. On middle of voltage divider R10/R11 I expect there will be 0 and MCU will not detect USB connection on (B).
The question is - would it work the way I described or I missed something? My concern is it ok to hook up only VCCIO to FTDI? Would it damage or lead to unknown behavior?