DESCRIPTION
An on-chip inverting op amp also allows monitoring one negative DC voltage. A single external capacitor sets the fault indication delay, eliminating false outputs due to switching noise, logic transition current spikes, and short-term AC line interruptions. An additional comparator referenced to 2.5V allows the AC line to be monitored for undervoltage conditions or for generation of a line clock. The comparator can also be used for programmable undervoltage lockout in a switching power supply. Uncommitted collector and emitter outputs permit both inverting and non-inverting operation. External availability of the precision 2.5V reference and