Programmable threshold data detection system

Abstract From the Canadian patent

A threshold detection circuit is provided for determining when a data input signal exhibits an amplitude which exceeds a first programmable threshold level, is less than a second programmable threshold level or between the first and second levels. Respective scaling circuits scale down the data input signal and a line voltage signal which is supplied to the circuit to generate a scaled data input signal and a scaled line voltage signal. The threshold detection circuit scales the first and second threshold levels by a predetermined factor. The scaled data input signal is compared with the scaled first and second threshold levels. In response to this comparison the output of, the circuit …