Phase detector measuring relative phase of periodic electrical signals - uses threshold switches receiving detector output coupled via switching device to switching logic controlling multivibrator output

摘要

The phase detector has bistable multivibrator (2) receiving the two output signals, coupled to a low-pass filter, providing a detector output, fed to a pair of threshold switches (14,15). The latter control a switching device (17) associated with a switching logic (6) allowing the signal fed to the setting input(s) of the bistable multivibrator to be switched to an inverted input signal. Pref. the switching device uses a JK flip-flop with the output coupled to the switching logic fed back to its J or K input, its clock input coupled to the outputs of the threshold switches via a NAND gate (16). ADVANTAGE - Extended linear measuring range and increased measuring accuracy.