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Timeline for Simulating a comparator circuit

Current License: CC BY-SA 3.0

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Apr 13, 2017 at 12:32 history edited CommunityBot
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Dec 31, 2016 at 6:25 answer added Ken Shirriff timeline score: 2
Dec 31, 2016 at 6:18 vote accept Kar
Dec 31, 2016 at 6:18 comment added Kar @KenShirriff You're right! Do you know why this happens without voltage rails?
Dec 31, 2016 at 6:05 comment added Ken Shirriff Try using an "op amp with voltage rails". I tried an op amp as a comparator in CircuitLab without rails, and it goes to +/- 60V as in your second diagram.
Dec 31, 2016 at 5:53 answer added Rohat Kılıç timeline score: 1
Dec 31, 2016 at 5:53 comment added Kar @PeterBennett The amplitude of the input is 5V. I'm measuring at the output of the LM339.
Dec 31, 2016 at 5:50 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:47 comment added Peter Bennett You now have reasonable timing, so you can see what's happening. What is the amplitude of the input signal, and where do you measure that 100 V p-p signal?
Dec 31, 2016 at 5:36 comment added Kar @KenShirriff I'm using CircuitLab. I just made some changes to this circuit (I can't save mine without a subscription!).
Dec 31, 2016 at 5:35 comment added Ken Shirriff What simulator are you using? Do you have power connected to the op amp?
Dec 31, 2016 at 5:35 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:28 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:23 comment added Kar @PeterBennett I've now tried 0.1ms steps over 10ms. Please see update.
Dec 31, 2016 at 5:23 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:21 comment added Peter Bennett You need to sample a few times per cycle - perhaps 0.1 mS would work. Then set the graph to show just a few cycles per square - perhaps 5 mS per square would show something useful.
Dec 31, 2016 at 5:21 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:17 comment added Kar @PeterBennett Granted, I've now set the stop time to 1 and a 1ms step. The output is still not a square wave though. Please see edit.
Dec 31, 2016 at 5:14 history edited Kar CC BY-SA 3.0
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Dec 31, 2016 at 5:10 comment added Peter Bennett If I'm reading things correctly, your signal is 1 KHz - one cycle per millisecond, but you are only sampling every 10 mS. The vertical lines on the graph are 500 mS apart, so you should get 500 cycles per square - pretty hard to see anything useful.
Dec 31, 2016 at 4:55 history asked Kar CC BY-SA 3.0