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What is wrong with comparator circuit

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bill-weilerBill Weiler 03/19/2018 at 06:140 Comments

Looking closer at the TI TL331 datasheet, I see I was fooled into thinking the offset voltage was 2mV. Looking closer it is this funny formula of VDD-1.5V. I think what it means is IN- and IN+ to the comparator, have to differ by more than (my voltage is 3V) 3-1.5=1.5V. Wow, I will never get that across a 1ohm resistor, I would need amps of current, not milliamps. 

Also, I think I have to deal with something, because I am self-taught PCB designer, my designs don't follow standards close enough. When I post to Stackexchange asking questions, I get dinged pretty hard for not following conventions in my schematics. Should be an easy thing to learn and fix, but it is building the habits that are hard. Also, I have to follow IPC standards. If I don't, I will confuse my suppliers, and spell doom.

Here is the schematic, the guy who answered said is was totally confusing because I didn't follow standards, and not using a preferred comparator symbol threw him.

Here is a link to Stackexchange question:

https://electronics.stackexchange.com/questions/363285/comparator-doesnt-swing-is-there-problem-with-circuit/363389#363389

Here is the schematic:

Doom .... doom....dooooom!

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