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:
Feb. 21, 2006
Filed:
Dec. 11, 2001
Michael S. C. Chung, San Jose, CA (US);
Michael S. C. Chung, San Jose, CA (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A switched capacitor controller accurately controls the rise time of an on-chip generated high voltage. An on-chip charge pump is used to generate a high voltage (VPP) from an external power supply voltage (VCC). This high voltage signal (VPP) can be used to program Flash memory cells. A capacitor of a switched capacitor circuit is selectively switched between ground and a given node voltage. This generates a stair-stepped ramp function. The period of the steps is controlled according to a clock signal. This clock signal may be altered to produce the desired period. The voltage increases of the steps is regulated by a reference voltage multiplied by a ratio between two capacitor values. Thereby, the rise-time of the ramp function is accurately controlled as a function of the frequency of the clock signal and the ratio of the two capacitor values.