Philips BJ2.4U Service Manual

Circuit Descriptions, Abbreviation List, and IC Data SheetsEN 128 BJ2.4U/BJ2.5U PA9.Figure 9-10 HDMI block diagramAudio, video, and auxiliary data is transmitted across the threeTMDS data channels. The video pixel clock is transmitted onthe TMDS clock channel and is used by the receiver as afrequency reference for data recovery on the three TMDS datachannels.Video data is carried as a series of 24-bit pixels on the threeTMDS data channels. TMDS encoding, converts the 8 bits perchannel into the 10 bit DC-balanced transition minimizedsequence, which is then transmitted serially across the pair ata rate of 10 bits per pixel clock period.Video pixel rates can range from 25 MHz to 165 MHz. Videoformats with rates below 25 MHz (e.g. 13.5 MHz for 480i/NTSC) can be transmitted using a pixel-repetition scheme. Thevideo pixels can be encoded in either RGB, YC BCR 4:4:4, orYCB CR 4:2:2 formats. In all three cases, up to 24 bits per pixelcan be transferred.In order to transmit audio and auxiliary data across the TMDSchannels, HDMI uses a packet structure. In order to attain thehigher reliability required of audio and control data, this data isprotected with a BCH error correction code and is encodedusing a special error reduction coding to produce the 10-bitword that is transmitted.Basic audio functionality consists of a single IEC 60958 audiostream at sample rates of 32 kHz, 44.1 kHz, or 48 kHz. This canaccommodate any normal stereo stream. Optionally, HDMI cancarry a single such stream at sample rates up to 192 kHz orfrom two to four such streams (3 to 8 audio channels) at samplerates up to 96 kHz. HDMI can also carry IEC 61937compressed (e.g. surround-sound) stream at sample rates upto 192 kHz.The DDC is used by the source to read the sink’s EnhancedExtended Display Identification Data (E-EDID) in order todiscover the sink’s configuration and/or capabilities.HDMI is backward compatible with DVI (1.0). Compared withDVI, HDMI offers extra:• YUV 4:4:4 (3 x 8-bit) or 4:2:2 (up to 2 x 12-bit), where DVIoffers only RGB 4:4:4 (3 x 8 bit).• Digital audio in CD quality (16-bit, 32/44.1/48 kHz), higherquality available (8 channels, 192 kHz).• Remote control via CEC bus (Consumer ElectronicsControl): allows user to control all HDMI devices with theTV's remote control and menus.• Smaller connector (SCART successor).• Less cables: e.g. from 10 audio/9 video cables to 3 HDMIcables.ImplementationThe IC used is the TDA9975 (triple 10-bit video converterinterface), item 7B11 on the SSB.• Power supply: 3V3 and 1V8.• Inputs:– HDMI connectors (Video, Audio, HDCP, Control).– Analogue (YPbPr, RGB, and H/V).• Control signals:– I 2 C coming from TDA9975 (MM-BUS1).– 13.5 MHz clock for analog format detection.– JTAG.• Output to PNX2015: Video (DV4 and DV5):– YUV 4:2:2 20 bit (10 bit Y, 10 bit UV multiplexed) +clock + sync.– ITU-656 (compressed DVD video) encoded in datastream.• Output to VIPER:– Audio: S/PDIF.– Interrupt signal.Data ContentFigure 9-11 Typical video frameA typical video frame is built up with the following info blocks:• Control Period.– Transmission of the pre-amble.– Character synchronization.• Data Island Period.– Audio and auxiliary information are carried in packetswithin a Data Island.– HSYNC, VSYNC are also carried during Data IslandPeriod.– Packet Types:– Audio Sample.– Audio Clock Recovery.– InfoFrame: Aux. Video IF, Audio IF, MPEG IF,vendor-defined IF.• Video Data Period.– Carries the pixels of an active video line.– TMDS encoding.Data Islands: Audio Formats• All current CE audio formats can be transmitted.• Supports compressed formats like:– Dolby Digital.– Dolby Digital EX (THX-EX).– DTS.– Etc.• Supports uncompressed formats (“discrete” PCM audio):– Up to 8 channels, up to 192 kHz, up to 24 bits.• CD-quality audio is always available, so the user willalways hear sound.– 2 channel, 16 bit at 32 kHz (STB), 44.1kHz (CD), or 48kHz (DVD)Data Islands: InfoFrames (EIA/CEA-861B)• Auxiliary Video Information (AVI):– Specifies active aspect ratio, colorimetric info, pixelencoding, etc.• Audio InfoFrame:– Describes audio stream, speaker/channel allocation,etc.• Source Product Info:HDMI SinkHDMI SourceVideoAudioVideoAudioTMDS Channel 0TMDS Channel 1TMDS Channel 2E_13950_062.eps120304Transmitter ReceiverTMDS Clock ChannelDisplay Data Channel (DDC)EDIDROMActive Video480 active lines525 total lines45 linesvertical blankingHSYNCVSYNCControlPeriodDataIslandPeriodVideoDataPeriodF_15400_011.eps210405