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Help with yet another comparator circuit

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imix500

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Hello all, I know there are a ton of these here but I didn't find the answer to my problem.
The input will be an LM35 but for know I'm using a fixed IN voltage to test.
My problem is when the output goes low, there is still .6v on the output which keeps enough current flowing through the transistor to keep the relay energized.
Thanks!
 

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  • Comparator..png
    Comparator..png
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R2 is demanding that IC1A is sinking 12 mA to keep the base of Q1 low. But LM393 only achieves its best output 'low' with less than 4 mA.

Increase R2 to 3.3K or more.
 
Replaced R2 with 4.7K and it's working perfectly now. Thanks!!

hi,
Your diagram shows the LM393 connected as an amplifier, not a comparator. Is it just a drawing error.??
 
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