DAVID A. MELLIS

MAS.863: How To Make (Almost) Anything

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Week 9: Output Devices

Color and Sound

Board with an RGB LED, photo-transistor, and buzzer (driven directly from a microcontroller pin). Download: color.sch, color.brd.
The board. The sound is rather quite, as expected when driving the buzzer from a microcontroller pin. The hope is to use the RGB LED and phototransistor as a color sensor.
Revised board. Download: color2.sch, color2.brd. Here the buzzer is driven with an N-MOSFET, and the LED pads are smaller (so the phototransistor can be closer).
Fading the RGB LED based on the light sensor readings. High ambient light -> low LED light.
And lower ambient light -> higher LED light.