View Full Version : Will 3.3 work on IOs of a PSC (Propeller Servo Controller)

03-29-2012, 02:52 AM
I ran out of cogs on my QuickStart board, so I decided to add a PSC board to my project, as I will be using servos.

I plan on using my own program on the PSC board, using some of its pins as in and outputs to communicate with the other propeller. Now I just realized that P0 to P15, as well at the serial connection, are all set for 5V -- and not 3.3V.

Will the PSC board be OK with a 3.3V pulses going in on any of the P-pins and/or the serial connection?

I assume that 3.3 should be OK for the serial IO if Vext is set to 3.3V (3.3 for Vcc on the Analog Switch 74VH1G66); however, for the P-pins (P0-P15) they are set for 5V. I see pin Vccv on the TXB0108PW bi-directional voltage translator is connected to 5V.

Will it work anyway for pin P0-P15? Or would it be better to go through a switch like a CD4016 to get from 3.3 to 5V?

Your suggestions are as always very welcome. Thanks! :smile: