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. 22, 2009
Filed:
Feb. 04, 2009
Menping Chang, Cupertino, CA (US);
Jing Tian, San Jose, CA (US);
Menping Chang, Cupertino, CA (US);
Jing Tian, San Jose, CA (US);
Micrel, Inc., San Jose, CA (US);
Abstract
A semiconductor relay switch having two data ports receiving incoming signals and a power supply terminal receiving a power supply voltage is responsive to a power supply voltage level and an energy level of the incoming signals to open and close its conduction paths. The relay switch is open when a valid power supply level is detected and when there is no supply power on the power supply terminal but a high energy level is detected in the incoming signals. The relay switch is closed to allow conduction between the two data ports only when there is no power supply voltage on the power supply terminal and an energy level below a predetermined threshold is detected in the incoming signals. In one embodiment, the semiconductor relay switch includes a main conduction switch circuit, an energy detect circuit and a control signal generator.