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:
Jul. 17, 2001
Filed:
Feb. 29, 2000
Applicant:
Inventors:
Jitendra Mohan, Sunnyvale, CA (US);
Devnath Varadarajan, Mountain View, CA (US);
Vijaya Ceekala, Union City, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03K 5/22 ;
U.S. Cl.
CPC ...
H03K 5/22 ;
Abstract
An RC calibration circuit, which utilizes a resistor and a variable capacitor connected in parallel, reduces power consumption and increases the accuracy of the calibration by comparing the voltage on the resistor to the voltage on the capacitor after a predetermined time has expired since the capacitor began charging up. The result of the comparison, which indicates whether the voltage on the resistor is greater than the voltage on the capacitor, is then used to adjust the capacitance of the capacitor to servo the RC time constant to a predetermined value.