Embedded Programming - Laser Driver

For this week, I made a laser driver circuit for my wearable display using the Atmel ATTiny85 mcu.


Designing the circuit on paper. The laser takes 400mA so you need to have a NPN BJT or MOSFET to drive it from the ATTiny85 mcu.


Designing the circuit in Eagle. For more info how to do circuit design, refer to "week 05: electronics design."

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Pictures of several attempts to make the board small. I added in right-angle JST connectors so I can attach a battery and laser to the board easily.


Programming the board via the 6-pin ISP header using Arduino.


Testing the board with 532nm green laser (5mW) and power supply (3.3v). Button triggers the laser on and off. If you hold it, the laser blinks.

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Here is a snapshot of how several of my components will come together for the final project: 3D printed wearable glasses, diffraction grating, and electronics :)


Special thanks and credit to Sparkfun for providing the right-angle JST connectors that made life much easier.