The MC14046B phase locked loop contains two phase comparators, a voltage-controlled oscillator (VCO), source follower, and zener diode. The comparators have two common signal inputs, PCAinand PCBin. Input PCAincan 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. Phase comparator 1 (an exclusive OR gate) provides a digital error signal PC1out, and maintains 90 phase shift at the center frequency between PCAinand PCBinsignals (both at 50% duty cycle). Phase comparator 2 (with leading edge sensing logic) provides digital error signals, PC2outand LD, and maintains a 0 phase shift between PCAinand PCBinsignals (duty cycle is immaterial). The linear VCO produces an output signal VCOoutwhose frequency is determined by the voltage of input VCOinand the capacitor and resistors connected to pins C1A, C1B, R1, and R2. The source-follower output SFoutwith an external resistor is used where the VCOinsignal is needed but no loading can be tolerated. The inhibit input Inh, when high, disables the VCO and source follower to minimize standby power consumption. The zener diode can be used to assist in power supply regulation.Applications include FM and FSK modulation and demodulation, frequency synthesis and multiplication, frequency discrimination, tone decoding, data synchronization and conditioning, voltage-to-frequency conversion and motor speed control.