Patent ID: 7449962
Filing Date: 2008-11-11
Classification: H03L

Abstract:
1. A phase-controlled current source for a phase-locked loop, wherein the phase-locked loop comprises a voltage-controlled oscillator to associate a charging path or discharging path to generate an output signal, and the output signal is sensed so as to generate a loop signal, the phase-controlled current source comprising: a status memory receiving the loop signal and a reference signal so as to output an energy-triggering/energy-removing signal; and a controllable current source, under the control by energy-triggering/energy-removing signal so as to decide whether a charging and discharging action should be performed, wherein after the charging action or discharging action is decided, the charging path or the discharging path is generated through the reference signal and the loop signal, wherein the status memory comprises a first switch, a second switch, a third switch and a fourth switch, which are serially connected between a high and low voltage side, wherein the reference signal is connected to the first switch and the third switch and the loop signal is connected to the second switch and the fourth switch, and wherein through the conducting of the non-conducting of the first switch, the second switch, the third switch and the fourth switch will output an energy-triggering/energy-removing signal between the second switch and the third switch.