SEMICONDUCTOR INTEGRATED CIRCUIT

摘要

PURPOSE: A semiconductor integrated circuit is provided to realize high speed operation in an integrated circuit by using a result which generated from a phase comparator is supplied to a voltage control generator in designing an integrated circuit. CONSTITUTION: A transforming signal circuit(10) is composed of a switch determining one choice of a common node(10a) changing node(10c) and changing node(10b). If a high level is gained from a carrier detector(11) the transforming circuit(10) connects the common mode(10a) to the changing node(10c), or to the changing node(10b). The phase comparator(12) is composed of an EX-OR and a R-S flip-flop so that the signal received from a 1/N divider(16) is compared. If the rising time is delayed low level voltage is supplied to a charge pumper(13) in direction of up, or is supplied to charge pumper(13) in direction of down. The charge pumper(13) determines the polarity supplied to a loop filter(14) which fillers an unnecessary high frequency and provides a current to the voltage control generator(15) which keeps the phase of an input signal to the phase of a desired signal.