Hitachi L32VK06U, Service Manual

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7 SIL9185 3:1 HDMI 1.3 Switch
7.1 General Description
The SiI9185A is the first generation of TMDS switch device supporting Revision 1.3 of the
HDMI Specification (HDMI Consortium; June 2006). With three HDMI inputs and a single
output, the SiI9185A provides a low-cost method of adding additional HDMI ports to the
latest Digital TVs. New DTVs can easily connect to the many HDMI sources coming on
the market, including DVDs, STB, game consoles, PCs, camcorders, and digital still
cameras. The SiI9185A is a fully HDMI compliant device providing a simple, lowcost
method of retransmitting protected digital audio and video, giving end-users a truly all-
digital experience. Built-in backward compatibility with DVI 1.0 allows HDMI systems to
connect to any DVI 1.0 source. The SiI9185A provides additional integrated features to
help lower system cost and provide enhanced features to the end consumer. To lower
system cost, the SiI9185A provides a complete solution for switching sink-side HDMI
signals. This includes DDC switching, individual HPD control, and 5V sense. The addition
of these features eliminates additional external components, helping to lower cost. For
source-side applications, the SiI9185A DDC switching can be bypassed with an external
4-channel I2C-bus switch(e.g., Texas Instruments PCA95445) to allow clock
stretching.
7.2 Features
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Three-input, single-output HDMI switcher
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Integrated TMDS® receiver and transmitt cores capable of receiving and
transmitting 2.25 Gbps:
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Support 60 Hz, 12-bit or 720p/1080i, 120 Hz, 12-bit
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Builcable support even at deep-color resolutions
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Pre-emphasi
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DVI 1.0, HDCP 1.1 and HDM compliant receiver and transmitter
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Uses HDMI-compliant TMDS core recovery and retransmission, unlike TMDS
switches, which use high-spee analog switches and degrade TMDS signals
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Built-in Cons support:
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HDM lowers cost for adding CEC support to DTV
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Integra requirements on system microcontrolle speeds design