Phase-locked loop frequency synthesizer

• Main Authors: NANJIAN WU, XIAOFEI KUANG
• Format: Patent
• Language: English
• Published: 01.06.2005
• Edition: 7
• Subjects: AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATIONOF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES; BASIC ELECTRONIC CIRCUITRY; ELECTRICITY

The phase locking loop frequency synthesizer includes one frequency discriminating phase detector, one charge pump with input connected to the output of the frequency discriminating phase detector, one low-pass filter with input connected to the output of the charge pump, one mixed digital and analog signal controlled vibrator accepting the signal from the low-pass filter and an N frequency dividing signal, and one 1/N frequency divider, and all the above said circuits constitute a phase locking loop. The mixed digital and analog signal controlled vibrator is controlled with the mixed digital and analog signal to realize fast frequency and phase locking; the digital signal determines the frequency of vibrator directly; and the analog signal controls the precision of the output frequency of the vibrator.