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:
Sep. 23, 1997
Filed:
Mar. 14, 1995
James Gorecki, Hillsboro, OR (US);
Ravindar Lall, Portland, OR (US);
Robert B Lefferts, Portland, OR (US);
Lattice Semiconductor Corporation, Hillsboro, OR (US);
Abstract
An embodiment of a pumped substrate system includes an oscillator, capacitive pump, comparing circuit, and a level shifter. The level shifter is coupled between the substrate and the positive input lead of the comparator and shifts the voltage level present on the substrate by a voltage Vbg. The comparator compares ground potential to the shifted substrate voltage. The oscillator, capacitive pump and comparing circuit form a negative feedback loop which operates to maintain the substrate voltage substantially equal to -Vbg. In one embodiment, the level shifter includes a band gap reference.