Patent · US Active

HDMI source detection

US8625029B2 · kind B2 · utility

4Cited by
3References
18Claims
0Family size

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Inventors

Key dates

Filing dateDec 17, 2007
Grant dateJan 7, 2014
Priority date
Expiry dateSep 4, 2031

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2370/047
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A circuit for detection of an HDMI source device to an HDMI sink device through an HDMI sink connector without regard for the activity state of the HDMI source device has a pull-up resistor having first and second terminals with the first terminal coupled to a DC power source. A switching device is coupled between the pull-up resistor's second terminal and ground at a circuit node. The switching device is switched on to couple the circuit node to ground when power is applied to a control terminal thereof from the HDMI sink connector power pin, and being switched off otherwise. The circuit node is coupled to a DDC/CEC GROUND pin of the HDMI sink connector. The circuit node is readable as a binary signal to indicate the presence of a source device to the HDMI sink connector, wherein the node exhibits a logic low signal when either the node is grounded by the DDC/CEC GROUND pin connection to a source device or when the switching device is switched on. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.