What to do with unused pins

[bryan]

I am using a LM339 comparator in a PWM circuit. I am only using 2 of the available 4 comparators on the chip. Should I tie tjhe other pins to ground or just leave as is.

 

[spuffock]

tie the +pins to +rail and the - pins to- rail . This forces the output pins open circuit and ensures that unused outputs dont flap about and generate nasty spikes.

 

[bryan]

Thank you

 

[Styx]

Also if this is a surface mount chip on a PCB tie the inputs via resitors (if it is a devel board and space isn't as important). You never know when a spare comparator might come in handy and it is a pain lifting legs and soldering onto them

just my 2 cents.