Embedded Programming - Laser Driver

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

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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.

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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.

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

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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 :)

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