Hello,

Please refer to the attached images. I have got the LM339's LTSpice model from https://github.com/evenator/LTSpice-Libraries/blob/master/sub/LM339.sub
I connected the circuit like that shown on the image and expected the output voltage, Vout, to be 0. However, the output is +5V. I would like to know if this is my mistake or something wrong with the model?

Thank You

 

Your pin-2 is connected to 0V.
The comparator cannot compare down to 0V with a single voltage supply.
Shift pin-2 upwards to some voltage higher than 0V.

 

You are exceeding the common mode input range. The inputs should be between 0V and 1.5V less than the supply voltage.

 

The comparator cannot compare down to 0V with a single voltage supply.
Shift pin-2 upwards to some voltage higher than 0V.

Worse, pin 3 is at -5V.

 

LM393 input transistors are PNP and ground is allowed:


The problem is the inverting input being at -5V.

 

Thank you guys! Your comments are very helpful. Actually, the voltage source V2 is a sinusoidal wave. I added a DC offset, so the wave will not swing below the ground.

 

Actually, the voltage source V2 is a sinusoidal wave. I added a DC offset, so the wave will not swing below the ground.

I just noticed that I mentioned LM393. It's the same comparator as LM339; it's just the dual version instead of quad.