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. 09, 1996
Filed:
Apr. 13, 1995
Brad D Gunter, Phoenix, AZ (US);
David Anderson, Scottsdale, AZ (US);
Danny A Bersch, Gilbert, AZ (US);
Howard C Anderson, Tempe, AZ (US);
Doug Garrity, Gilbert, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A circuit and method for reducing voltage error when charging and discharging a variable capacitor (44) through a switch (43). The switch (43) comprises a plurality of transmission gates (53-55) coupled in parallel. A control circuit (42) provides control signals for enabling transmission gates of the plurality of transmission gates (53-55). The control circuit (42) changes the resistance of the switch (43) by selecting an appropriate transmission gate wherein each transmission gate has a different resistance. The resistance of the switch (43) is varied as a capacitance of the variable capacitor (44) is changed to maintain a predetermined RC time constant over the entire range of capacitor values of the variable capacitor (44).