The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 2020
Filed:
Dec. 20, 2019
Taiwan Semiconductor Manufacturing Co., Ltd., Hsinchu, TW;
Ting-Kuei Kuan, Taichung, TW;
Cheng-Hsiang Hsieh, Taipei, TW;
Chen-Ting Ko, Hsinchu, TW;
Ruey-Bin Sheen, Taichung, TW;
Chih-Hsien Chang, New Taipei, TW;
TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD, Hsinchu, TW;
Abstract
Phase-locked loops (PLLs) are provided. A PLL includes a voltage-controlled oscillator (VCO), a frequency divider, a track-and-hold charge pump, and a frequency tracking circuit. The VCO is configured to provide an output clock corresponding to a pumping current. The frequency divider is configured to divide the output clock to provide a feedback signal. The track-and-hold charge pump is configured to provide the pumping current according to a reference clock and the feedback signal. The frequency tracking circuit is configured to decrease frequency error between the feedback signal and the reference clock. The track-and-hold charge pump includes a pumping switch and a pulse width modulator (PWM). The PWM is configured to provide a PWM signal to control the pumping switch according to the reference clock, so as to provide the pumping current corresponding to the feedback signal.