QT Py Microcontroller form factor

The QT Py microcontroller form factor is a common form factor in the low-cost microcontrollers used by MMC, such as the Seeed Studio XIAO nrf52840 used in the LipSync, or the Adafruit SAMD21 QT Py used in the Forest Hub. It is also used in devices such as the Ivy Joystick where it is not soldered to a PCB but instead held in place with a snap fit.

Angled shot of QT Py.

Although it is most commonly attached to a PCB with headers, it is sometimes useful to know the primary dimensions for attaching it through snap fits, slide rails, or other methods. The primary dimensions are as follows.

  • Board Length: The length of the board PCB.
  • Board Width: The width of the board PCB.
  • Board Thickness: The thickness of the board
  • USB C Port Protrusion: The distance that the USB connector protrudes past the edge of the board PCB.
  • Base of Board to Center of USB Port: This is the distance from the bottom of the board PCB to the centre of the USB C port connector. This distance is useful for determining the position of a knockout for the USB connector

A top view of the QT Py with the length and width labeled. A side view of the QT Py with the key dimensions labeled.

QT Py Form Factor Measurements  
Board Length 20.6 mm
Board Width 17.8 mm
Board Thickness 4 mm
USB C Port Protrusion 1.5 mm
Base of Board to Center of USB Port 2.9 mm