Patent ID: 6154096
Filing Date: 2000-11-28
Classification: H03L

Abstract:
A charge pump phase comparator for a phase locked loop having a phase detector pumping a loop filter to derive a control voltage for a voltage controlled oscillator, comprising:a phase detectora charging amplifier for charging said loop filtera discharging amplifier for discharging said loop filter;a command for selecting said charging amplifier and discharging amplifier to be activated;a reset means for setting said charging amplifier in condition for charging said loop filter and for setting said discharging amplifier for discharging said loop filter;a first latch between said charging amplifier and said reset means to speed up the reset means; anda second latch between said discharging amplifier and said reset means to speed up the reset means,wherein each of said first latch and said second latch comprises two cross-coupled inverters having a first output node A and second output node B.