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:
Dec. 19, 2006
Filed:
Sep. 16, 2004
Dan D'aquino, Sunnyvale, CA (US);
Mehmet Aslan, Sunnyvale, CA (US);
Dan D'Aquino, Sunnyvale, CA (US);
Mehmet Aslan, Sunnyvale, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A method and circuit for reducing a temperature dependent error in p-n junction based temperature measurements. The temperature-dependent error may be caused by parasitic resistance in a p-n junction and temperature dependent variation of a bias current in a temperature sensor. A difference in base-emitter voltage of a sensing transistor is employed to determine a temperature of a source device. In one embodiment, a zero Temperature Coefficient (TC) current source employing a temperature dependent variation of a current generates by an emitter-base voltage across a resistor between the emitter and the base of a junction transistor is used to counter balance a Proportional To Absolute Temperature (PTAT) current source.