Phase control circuit for wireless communication equipment, has voltage controlled oscillator, phase comparator creating first control signal, control unit creating second control signal, and control signal selector switching

摘要

The circuit (100) comprises a voltage controlled oscillator (101) for generating an output signal according to a selected control signal. A feedback unit (102) is provided for feeding back the output as a feedback signal. A phase detector creates a first control signal according to the phase difference between the feedback signal and a reference signal. A control unit (105) creates a second control signal, according to the desired output frequency. A switching circuit (106) selects the first or second control signal, according to a control signal. - In the phase control circuit (100) adjustment of an output signal (111) with a desired frequency takes place first in an open loop control operation and then in an automatic closed loop control operation. Changeover from one to the other takes place when the voltages of a first control signal (113) and a second control signal (115,118) ,within a specific range. Independent claims are included for a personal computer memory card for contact-less data transmission, a base station, a mobile unit, and a method of generating an output signal with an adjustable frequency.