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1
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1answer
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Phototransistor as a pull-down in digital circuit

I have very little experience with phototransistors. I'm trying to create a circuit that will effectively function as collision detection. I'm using OPB608A which utilizes an NPN transistor. My goal ...
8
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7answers
3k views

Which configuration is better for pulling down an NPN transistor's base?

I was discussing on pull down resistors with a colleague of mine. Here are the two configurations for transistor as a switch. The input signal can either come from a microcontroller or an another ...