Plugin PCB board teensy for old board with Nano

[Pat]

I have made some hats for v2/kaupoi boards last winter.
I have used one with ethernet all year long.

Compact Teensy single GPS hat for autosteer PCB

I decided to draw a PCB to mount the future all in one Teensy synchronized GPS/IMU +autosteer code to my existing PCB’s. So it plug in the Arduino heaters and make a compact assembly. It could also be used as GPS only module with correct supply. I have just a little knowledge in hardware so every comments are welcome if someone see a mistake or have idea to improve design. First thing is Teesy run on 3.3V while Autosteer PCB is on 5V. So I put a Sparkfun PCA9306 for the i2c, PN2222 transistor…