Title:
HIGH-PRECISION FREQUENCY CALIBRATION CIRCUIT USED FOR GM-C FILTER
Document Type and Number:
WIPO Patent Application WO/2016/138807
Kind Code:
A1
Abstract:
Provided is a Gm-C filter frequency-calibration circuit having low power consumption and high calibration precision; the frequency calibration circuit comprises four modules: a clock generation circuit, a sample-and-hold circuit, a master transconductance amplifier (Gm), and an error amplifier (OTA2). The master transconductance amplifier (Gm) in the master-slave structure control calibration circuit matches the slave transconductance amplifier in the Gm-C filter, and is controlled by the same bias voltage. The error of the frequency characteristics of the Gm-C filter is influenced primarily by such factors as the transconductance value of the transconductance amplifier, the process variation of the capacitance, and temperature; the consideration of the frequency characteristics of the Gm-C filter is determined primarily by the time constant Gm/C thereof; by means of converting the transconductance value Gm of the transconductance amplifier into a variable having an accurate directly proportional relationship with the capacitance C, the influence of the process variation of the capacitance on the time constant Gm/C is eliminated, allowing for very high calibration accuracy; the invention has the features of a simple structure, low power consumption, and a small chip area, and is also highly stable.
Inventors:
WU JIANHUI (CN)
YU TIANJI (CN)
CHENG CHAO (CN)
YAO HONGYAN (CN)
CHEN CHAO (CN)
LI HONG (CN)
HUANG CHENG (CN)
YU TIANJI (CN)
CHENG CHAO (CN)
YAO HONGYAN (CN)
CHEN CHAO (CN)
LI HONG (CN)
HUANG CHENG (CN)
Application Number:
PCT/CN2016/072564
Publication Date:
September 09, 2016
Filing Date:
January 28, 2016
Export Citation:
Assignee:
UNIV SOUTHEAST (CN)
International Classes:
H03H17/02
Foreign References:
| CN104660216A | 2015-05-27 | |||
| CN103905037A | 2014-07-02 | |||
| CN102006095A | 2011-04-06 | |||
| US8373502B1 | 2013-02-12 | |||
| JP2002223148A | 2002-08-09 |
Attorney, Agent or Firm:
NANJING JINGWEI PATENT & TRADEMARK AGENCY CO., LTD (CN)
南京经纬专利商标代理有限公司 (CN)
南京经纬专利商标代理有限公司 (CN)
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