Title:
広い周波数範囲を持つCMOS電圧制御発振器
Document Type and Number:
Japanese Patent JP3591841
Kind Code:
B2
Abstract:
A voltage controlled oscillator (VCO) which may be adjusted to provide oscillatory signals for a wide range of frequencies includes a relaxation oscillator in which a ramp signal is compared to a reference threshold which exhibits hysteresis. The frequency of the oscillator is changed by varying the hysteresis range of the threshold level and by changing the rate at which the ramp is generated. At higher frequencies, the signal processing delay through the comparator is a factor in determining the frequency of the signal produced by the oscillator. Current sources internal to the oscillator are controlled by a reference potential that is generated from an externally supplied band-gap reference potential. The VCO is used in a phase-locked loop which includes a charge pump circuit that accumulates charge on a capacitor responsive to limited-width pulses applied to a current source which is controlled by the reference potential generated in the VCO.
Inventors:
Soea, Donald, Jay.
Application Number:
JP51890396A
Publication Date:
November 24, 2004
Filing Date:
December 08, 1995
Export Citation:
Assignee:
Sarnoff Corporation
International Classes:
H03K3/0231; H03K3/354; H03K5/26; H03L7/089; H03L7/099; (IPC1-7): H03K3/0231; H03K3/354; H03K5/26; H03L7/099
Domestic Patent References:
| JP4133113A | ||||
| JP63299407A |
Attorney, Agent or Firm:
Yoshiki Hasegawa
Tatsuya Shioda
Shiro Terasaki
Yuichi Yamada
Okimoto Kazuaki
Ichira Kondo
Tatsuya Shioda
Shiro Terasaki
Yuichi Yamada
Okimoto Kazuaki
Ichira Kondo