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. 19, 2008
Filed:
Jun. 08, 2006
Guy P. Bouchard, Beverly, MA (US);
John E. Cross, Needham, MA (US);
Guy P. Bouchard, Beverly, MA (US);
John E. Cross, Needham, MA (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
A temperature sensing circuit for a ballast for a HID lamp multiplexes the temperature measurement function with another function to reduce the number of pins required for the temperature measurement function performed by the microcontroller of the ballast. The circuit includes a microcontroller having a first A/D input/output pin, a second A/D input/output pin and a multifunction pin, a temperature measurement circuit connected to the second A/D pin, a timing circuit connected to the first A/D pin, and a switch connected to the multifunction pin, temperature measurement circuit and timing circuit. The switch activates the temperature measurement function by connecting the temperature measurement circuit to the multifunction pin in a first position and deactivates the function by disconnecting the temperature measurement circuit from the multifunction pin in a second position.