Get rid of parasitic UART power

[pulurumbuluruciu]

Hi , I`m having a problem with parasitic power on my 18f PIC. I have a power switch to turn ON/OFF the circuit but it wont work because with a PL2032 USB/UART converter the PIC gets parasitic power and never turns off...with a FTDI such thing is not happening..but is way more expensive in the long run..Is there a simple solution to get rid of that parasitic power when using a cheap 2032 converter? Thank you very much

[newguy]

If the parasitic power is coupling into your board's Vcc, then perhaps a PIC controlled high side switch (PMOS FET) Vcc -- FET -- PL2032 would do the trick. If the power is being drawn on the RX/TX line(s), a simple 100R series resistor(s) between PIC and PL2032 should suffice.

[pulurumbuluruciu]

Hi , thank you, the 100R resistor did not work , however with a 2KOhm resistor it works , no more parasitic power , yey thank you again