I'm doing a circuit, I was helped by wayneh to figure it out. It works in SIM, but I don't understand how or why. I have 2 comparators configured in a OR, according to LM393 datasheet.
Now, this confuses me. I understand that *what supposedly happens* is that if either comparator goes high, the output goes high. The way I see it though, these comparator outputs are open collector, so with the pullup resistor, the output should be high if both comparators are low. If one of them goes high, it will sink the current and the output will go low. I know I'm wrong, but I have no clue why I'm wrong. can someone set me straight?
What confuses me further is that this actually functions as an AND gate in my sim. When both of my comparators are high, the output is high. When I send one of my comparators low, the output is low. WTH?
Now, this confuses me. I understand that *what supposedly happens* is that if either comparator goes high, the output goes high. The way I see it though, these comparator outputs are open collector, so with the pullup resistor, the output should be high if both comparators are low. If one of them goes high, it will sink the current and the output will go low. I know I'm wrong, but I have no clue why I'm wrong. can someone set me straight?
What confuses me further is that this actually functions as an AND gate in my sim. When both of my comparators are high, the output is high. When I send one of my comparators low, the output is low. WTH?
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