Window Detector using LM339

[abbeyromy]

Hi,

I was trying to make a window detector circuit with threshold values 5V(Lower) and 10V(upper). Please see the attached circuit and output wave.

As per my understanding the output is open collector and thus wired OR configuration can be used. The problem is that the output does not fall to zero after the input goes above 10 V.

Any suggestions?

Thanks for the help
-Hemanshu

 

[FvM]

By the specification, the LM339 output is not guaranteed to sink more than 4 mA. So an 1K load resistor is too low. But I guess,
the problem in your simulation setup is, that you have to conncet all supply pins. Altough the individual comparators show pin
numbers of the real device, they are represented by different model instances with separate supply pins.

 

[abbeyromy]

Hey FvM, thanks yes it is working now.

The key was to connect all supply to all the parts. I was thinking that since supply pins are shorted so giving to one would automatically support everybody.

Thanks a lot!
-Hemanshu