Gyroscreen

Gyroscreen: Hardware

In this README you will find the documentation about the hardware part of the project.

Electric design and PCB

The 3 KiCAD files present in this directory have been created using KiCAD v8.0 and represent the hardware of the project.

Electric design

The electric design consists of an ATTiny85 and a accelerometer and gyroscope sensor: MPU6050. They communicate using I2C, and the AVR board communicates with the computer using the USB protocol.

Due to the requirements of the sensor I had to put a Step-Down regulator in order to reduce the 5V USB power to 3V3. USB D+ and D- need also to communicate through 3.3V, that's why there are two Zener diodes there.

I'm not going to lie: this schematic is a combination (with only the parts I needed) of the Digistump's Digispark and the GY-521 accelerometer sensor module. They did the hard work.

PCB

This is a very simple PCB, where I just payed attention to leave a bigger track size for the power lines, and checked that every footprint was available in JLCPCB.

The main motivation on using an USB-C connector is to comply with future EU regulations.

Obtaining the PCB

I printed the PCB in JLCPCB for less than $1 each unit. The most expensive part was the component placing (I was too lazy to do it myself) and shipping fees. Here are some front and back pictures:

3D-Printed enclosure

In this directory you will also find files regarding a 3D enclosure for the board. As it needs to be sticked to the back of the screen, taking dust and be touched by dirty fingers, it's safer to have it in a closed rectangle.

That's what the design is. A rectangle with a hole for the USB-C connector.

Once printed it looks something more professional: