I'm helping some friends build a device. My part of the job is to turn on the transistor when the UV Output <6< gets up to .2v.
I tried an MCP6231 and it worked. The problem was their device uses 12v. and the max on that Op-Amp supply is 6v. I made it
work with a voltage divider but wanted to simplify this to the max. I thought using an LF356N might work like the MCP6231 but
it doesn't. I'm running the +12v right to pin 7 vss. I thought Op-Amps would adjust the output so that the voltage on pin 2 would
be the same as on pin 3. If that were the case, I would think the output at pin 6 would go to 1v. to get the voltage on pin 2 at .2v.
Then as long as the flow switch is closed, the 1v. should turn on the 2N2222.
I'm missing something. Help would be greatly appreciated.
I tried an MCP6231 and it worked. The problem was their device uses 12v. and the max on that Op-Amp supply is 6v. I made it
work with a voltage divider but wanted to simplify this to the max. I thought using an LF356N might work like the MCP6231 but
it doesn't. I'm running the +12v right to pin 7 vss. I thought Op-Amps would adjust the output so that the voltage on pin 2 would
be the same as on pin 3. If that were the case, I would think the output at pin 6 would go to 1v. to get the voltage on pin 2 at .2v.
Then as long as the flow switch is closed, the 1v. should turn on the 2N2222.
I'm missing something. Help would be greatly appreciated.
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