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Member Since: June 6, 2012

Country: Canada

  • Hi Jimb0,

    I'm currently adding the FT231X onto one of my boards. I got in contact with an engineer at FTDI and he said that the FET that you have on the DTR line is unnecessary. Supposedly as long as you have a voltage appropriate pullup resistor of 10K or greater, DTR should be able to pull down the line effectively.

    Since the higher voltage of the pullup overrides the 3.3V of the DTR line, you shouldn't have any issues with a "logic high".

    This of course is only applicable for voltages of 5V or less.


  • Hey guys,

    Thought I would point out that there is an error in the schematic with regards to how you have connected the DC barrel jack pins.

    Ground should be connected to pin 2 of the barrel jack rather than pin 3 as the schematic currently shows.

    With the current configuration, when the connector is inserted, the barrel is no longer connected to ground which means that the circuit has no reference. The design would only work with USB power.

No public wish lists :(