Patent ID: 7239102

Claim:
A phase adjustment circuit which inputs sine wave signals of a first phase, second phase and third phase in which a phase difference between the respective first, second and third phases is 120°, and which adjusts the phases of the sine wave signals by a phase adjustment voltage, and outputs sine wave signals of the first phase, second phase and third phase, wherein a signal, which is obtained by computing the input sine wave signal of the first phase with the input sine wave signal of the second phase or third phase multiplied by a ratio corresponding to the phase adjustment voltage, is output as the sine wave signal of one of the first, second and third phases; a signal, which is obtained by computing the input sine wave signal of the second phase with the input sine wave signal of the third phase or first phase multiplied by said ratio, is output as the sine wave signal of one of the first, second and third phases; and a signal, which is obtained by computing the input sine wave signal of the third phase with the input sine wave signal of the first phase or second phase multiplied by said ratio, is output as the sine wave signal of one of the first, second and third phases.