The attached picture shows how a switching transistor can use the 1v from a solar cell to turn on a light. Is it possible to reverse the transistor so that the switch turns on when no light is present? In other words, do transistors come in "normally closed" and "normally open" versions? I need to put both types in my circuit. If the sun is shining, I need current to flow in one part of my circuit while blocking the flow of current in another part of my circuit. Conversely, when the sun is not shining, I need the opposite to be true.
Is the above the difference between npn and pnp?
Thanks,
Is the above the difference between npn and pnp?
Thanks,
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