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. 03, 1991
Filed:
Oct. 01, 1990
Kunio Nishiwaki, San Jose, CA (US);
Kevin A Norman, Belmont, CA (US);
Altera Corporation, San Jose, CA (US);
Abstract
A circuit and method for generating a reference voltage which decreases as a supply voltage increases, and increases as the supply voltage decreases are provided. The circuit includes a voltage divider connected to the input of an inverting amplifier whose output is connected to a level shifter/buffer. Increases in the supply voltage cause the output voltage of the voltage divider and hence the input voltage of the inverting amplifier to increase. Over the operating range, the combined effect of the increasing input and supply voltage cause the output voltage of the inverting amplifier to decrease. Similarly, over the operating range, a decrease in supply voltage causes an increase in output voltage from the inverting amplifier. This output voltage is shifted to a level more convenient for the user by the level shifter/buffer. The buffer also increases the amount of output current that can be supplied by the reference voltage generator.