Analog Multipliers-Based Double Output Voltage Phase Detector for Low-Frequency Demodulation of Frequency Modulated Signals

This work deals with the design of a simple double output voltage phase detector, using specific type analog multiplier, and its application in frequency demodulator. The active parts was performed Taiwan Semiconductor Manufacturing Company (TSMC) $0.18~\mu \text{m}$ 1.8 V CMOS technology. intention is devoted to circuitry such way avoid low-frequency signal processing large values capacities that are not available case on-chip implementation. idea consists significantly faster (tens kHz) carrying modulated low information. Then coupling capacity may have smaller value. operation demodulator tested for carrier 50 kHz modulation 10 Hz 500 Hz. Differences these frequencies approximately determine capacitors required AC coupling. Simulations (Cadence Spectre simulator) as well experimental measurement, fabricated ASIC prototypes, provided verify proposed circuits both time domain.