I am considering powering the VDD input to the JTAG-SMT3-NC module from the USB supply instead of the device's power supply. Of course this will require a 3.3V LDO to bring VDD down. Do you see any issue with doing that?
In my case, I would have:
VDD - 3.3V from LDO from USB V+ (when cable plugged in)
VREF_UART = 3.3V from system power supply (on when board powered up)
VREF_JTAG = 1.8V from system power supply (on when board powered up)
My intention is to allow the UART connection over USB to stay connected even when power cycling the board. I ask because all of the documents show VDD being supplied from the system, not USB.
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jmcexx
I am considering powering the VDD input to the JTAG-SMT3-NC module from the USB supply instead of the device's power supply. Of course this will require a 3.3V LDO to bring VDD down. Do you see any issue with doing that?
In my case, I would have:
VDD - 3.3V from LDO from USB V+ (when cable plugged in)
VREF_UART = 3.3V from system power supply (on when board powered up)
VREF_JTAG = 1.8V from system power supply (on when board powered up)
My intention is to allow the UART connection over USB to stay connected even when power cycling the board. I ask because all of the documents show VDD being supplied from the system, not USB.
Thanks for any thoughts!
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