topic K22-120: Can VDD=1.8V if using USB interface? in Kinetis Microcontrollers

K22-120: Can VDD=1.8V if using USB interface?

matthew_pattiso — Thu, 31 Oct 2019 16:57:37 GMT

I am working on a K22-120 design. I need the USB (device only) interface but also have a bunch of GPIO that needs to be 1.8V. Can I power the USB via the VREGIN with 5V, but connect the VDD pins to a 1.8V power supply such that all of my GPIO (I2C, SPI, etc..) will be 1.8V. I am trying to avoid level translators on my gpio for space reasons.

Re: K22-120: Can VDD=1.8V if using USB interface?

jingpan — Fri, 01 Nov 2019 08:27:57 GMT

Hi Matt,

yes, it can. VREGIN should connect to USB VBUS, but VOUT33 connect to ground with a capacitor. Then you can connect VDD to 1.8v.

Regards,

Jing