Title:
PLL FREQUENCY SYNTHESIZER
Document Type and Number:
WIPO Patent Application WO/2018/216148
Kind Code:
A1
Abstract:
This PLL frequency synthesizer is provided with: a voltage-controlled oscillator which outputs an oscillation signal having a frequency corresponding to a control voltage value; a phase comparison unit which inputs, as a feedback oscillation signal, the oscillation signal or a signal obtained by frequency-dividing the oscillation signal and which detects a phase difference between the feedback oscillation signal and a reference oscillation signal and then outputs a phase difference signal representing the phase difference; a charge pump which outputs a charging/discharging current corresponding to the phase difference represented by the phase difference signal; a loop filter which includes a capacitative element that is charged/discharged upon input of the charging/discharging current thereto and which outputs, to the voltage-controlled oscillator, a control voltage value that is incremented/decremented in accordance with the charge/discharge amount of the capacitative element; a detection unit which detects the rate of change in the control voltage value when the charging/discharging current is inputted to the loop filter; and a control unit which, according to the detection result of the detection unit, makes adjustments to the charging/discharging current, the characteristics of the loop filter, or the characteristics of the voltage-controlled oscillator.
Inventors:
KUBO SHUNICHI (JP)
Application Number:
PCT/JP2017/019407
Publication Date:
November 29, 2018
Filing Date:
May 24, 2017
Export Citation:
Assignee:
THINE ELECTRONICS INC (JP)
International Classes:
H03L7/18; H03L7/10
Foreign References:
| JP2013016995A | 2013-01-24 | |||
| JP2016178351A | 2016-10-06 | |||
| JP2004241933A | 2004-08-26 | |||
| JP2005312028A | 2005-11-04 |
Attorney, Agent or Firm:
HASEGAWA Yoshiki et al. (JP)
Download PDF:
Previous Patent: COMPONENT GRIPPING TOOL
Next Patent: DEVICE FOR DETECTING ROTATION ANGLE AND DEVICE FOR CONTROLLING AC ROTARY MACHINE
Next Patent: DEVICE FOR DETECTING ROTATION ANGLE AND DEVICE FOR CONTROLLING AC ROTARY MACHINE