PSOC4 or PSOC5LP mixed voltage IO

[chro_1316281]

I have a project I am working on where I need to interface via I2C or SPI to 3.3v device(not 5v tolerant)  and also have some GPIO that is 5v.

I have CY8CKIT-049-42xx kits as well as CY8CKIT-059 kits to work with. I am fine with having to snap off the KitProg once programmed, if necessary. I am fine powering the board with either 3.3v or 5v whichever is easier to work with.

I have read thru a lots of posts and the GPIO and other cypress notes. It looks like the PSOC5LP might be able to do this via VDDIOX pins, but they seem to be all joined on the CY8CKIT-059 kits. I did find a few articles of running the whole board at 3.3v, but I also need a number of 5v GPIO's.

I can't really find anything on the CY8CKIT-049-42xx kits on 3.3v operation.

Any thoughts would be appreciated.

Thanks,
Chris

[odissey1 · Accepted solution]

Chris,

For 3.3V SPI / I2C you can use Special Pins (Port 12 on KIT-059), which can be configured to any voltage in the Output section (Vref). Then it is up to you to provide 3.3V Vref voltage.

See also

AN60580 - SIO Tips and Tricks in PSoC® 3 / PSoC 5LP

/odissey1

[chro_1316281]

Great thanks. I figured I just missed something.

Chris