Patent ID: 7336147
Filing Date: 2008-02-26
Classification: H01F,H01L

Abstract:
1. An IC chip comprising: a first inductor provided on a semiconductor substrate; a second inductor provided on the semiconductor substrate so as to be magnetically coupled to the first inductor; a current source whose current is variable, electrically connected to the first inductor; a frequency divider for dividing a frequency of a feedback signal having frequency information in a current flowing in the second inductor to a predetermined frequency; a phase detector for comparing a phase of the frequency divided signal with a phase of a reference signal having predetermined frequency information; and a charge pump for outputting a voltage to the current source according to an input from the phase detector, wherein the first and second inductors, the current source, the frequency divider, the phase detector, and the charge pump are constituted as a semiconductor integrated circuit, and the current source adjusts a value of the current according to an input signal from the charge pump.