Hi
I'm trying to use an LM339 Quad Op Amp as 4 comparators for making a light intensity sensor (LED,LDR pair). The problem is, if i bias the non-inverting input(reference) to half d Vcc, when i change the inverting input, the ouput gradually changes from 0 to Vcc/2, instead of abrupt change from 0 to Vcc. In fact I checked the voltage at the non-inverting reference: instead of remaining at Vcc/2 all the time, it changes linearly as the inverting input voltage is changed!! What's wrong??
Thanks guys.
I'm trying to use an LM339 Quad Op Amp as 4 comparators for making a light intensity sensor (LED,LDR pair). The problem is, if i bias the non-inverting input(reference) to half d Vcc, when i change the inverting input, the ouput gradually changes from 0 to Vcc/2, instead of abrupt change from 0 to Vcc. In fact I checked the voltage at the non-inverting reference: instead of remaining at Vcc/2 all the time, it changes linearly as the inverting input voltage is changed!! What's wrong??
Thanks guys.