Phototransistor breakout board

2017 May 01
#electronics  #cut2d  #elecFab 

In a previous project based on an ATtiny44 I added an expansion pin on PA2 (ADC2/AIN1/PCINT2). I think I can use that pin to take readings from a phototransistor; making this a nice little project to get generate some momentum. Remember: spiral development.

First I examined Neil Gershenfeld's ATtiny45 schematic, the ATtiny45 datasheet, the ATtiny44 datasheet, andthe OP580DA phototransistor datasheet.

Because both pins are compatible with Analog to Digital Conversion (ADC), the phototransistor should work with my ATtiny44 board. The first step is to design a board for the phototransistor, resistor, voltage, ground, and logic connections. I use Autodesk's Eagle.

Relatively simple schematic. One thing to be aware. The phototransistor is directional. You can check the datasheet for that. Hint the chamferred corner aligns with the collector side.

Out comes the traces and interior (linked below for download).

A quick milling job.

Cleaned up and stuffed.

Want to make one? You can do that.

Download project files

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Next post :: Phototransistor : reading »

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