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:
Oct. 10, 2000
Filed:
Aug. 08, 1997
Timothy M Lacey, Cupertino, CA (US);
Khaldoon Abugharbieh, Sunnyvale, CA (US);
Cypress Semiconductor Corporation, San Jose, CA (US);
Abstract
A voltage source is configured to produce a desired voltage and the desired voltage is applied to a programmable cell coupled to the voltage source. Configuration may be accomplished by loading a register with a programmed voltage value which may be received as a serial data stream through a test access port coupled to the register. For one embodiment, the voltage source may be coupled to a gate of the programmable cell, thus allowing testing of margin voltages of the programmable cell. In a further embodiment, the voltage source may be coupled to a drain of the programmable cell through a load line circuit, thus providing a programmed voltage for the programmable cell. In general then, the programmable voltage source is configurable to provide a voltage to the programmable cell in accordance with a programmed voltage value loaded into the programmable voltage source. The present invention may be embodied in a programmable device such as a PLD a CPLD or an FPGA and provides easily adjustable verify and/or program voltages, configurable through use of the programmable register, to test the operation of the programmable cell. The higher the bit count of the register, the more precise a verify and/or program voltage that may be provided.