Click to expand full text
MC74HC4046A Phase-Locked Loop
High–Performance Silicon–Gate CMOS
The MC74HC4046A is similar in function to the MC14046 Metal gate CMOS device. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LSTTL outputs. The HC4046A phase–locked loop contains three phase comparators, a voltage–controlled oscillator (VCO) and unity gain op–amp DEMOUT. The comparators have two common signal inputs, COMP IN, and SIG IN. Input SIG IN and COMP IN can be used directly coupled to large voltage signals, or indirectly coupled (with a series capacitor to small voltage signals). The self–bias circuit adjusts small voltage signals in the linear region of the amplifier.