Title:
A SWITCHED-CAPACITIVE CIRCUIT AND METHOD FOR REDUCING CLOCK FEEDTHROUGH IN VOLTAGE CONTROLLED OSCILLATOR
Document Type and Number:
WIPO Patent Application WO/2004/107558
Kind Code:
A1
Abstract:
A switched-capacitive circuit, used in a voltage controlled oscillator, for reducing the clock feedthrough effect, by which instantaneous frequency drift caused was reduced.Said switchedÂcapacitive was switched from a gateway status to a turnoff state gradually, then the clock feedthrough effect was reduced to the least.A pularity of switch members which have different size were used to switch a capacitance from an internal capacitance node to a grounded node. When said switched-capacitive circuit was switched to the turnoff state, a pularity of control signal will be switched in order, in accordance with the size of switch members. Said switch member were gradually opened according to their decreasing volume. Moreover, a lowpass could be set at the front of controlling of the least switched-module for further reducing the clock feedthrough effect.
Inventors:
HSIAO CHI-MING
DEHNG GUANG-KAAI
TSAI MING-HORNG
KE LING-WEI
YEH EN-HSIANG
CHI CHI-KUN
DEHNG GUANG-KAAI
TSAI MING-HORNG
KE LING-WEI
YEH EN-HSIANG
CHI CHI-KUN
Application Number:
PCT/CN2004/000599
Publication Date:
December 09, 2004
Filing Date:
June 03, 2004
Export Citation:
Assignee:
MEDIATEK INC (CN)
International Classes:
G06F7/64; G06G7/18; G06G7/19; H03B5/00; H03B5/12; H03K17/00; (IPC1-7): H03B5/00
Foreign References:
| JPH10209752A | 1998-08-07 | |||
| US20020135428A1 | 2002-09-26 |
Attorney, Agent or Firm:
LIU, SHEN & ASSOCIATES (Huibin Building No. 8 Beichen Dong Stree, Chaoyang District Beijing 1, CN)
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