 |
数据搜索系统，热门电子元器件搜索 |
|
|
数据搜索系统，热门电子元器件搜索 |
|
AD9381 数据表(PDF) 10 Page - Analog Devices |
|
||||||||||||||||||||||||||||||
AD9381 数据表(HTML) 10 Page - Analog Devices |
|
|
10 / 44 page  AD9381 Rev. 0 | Page 10 of 44 TIMING The output data clock signal is created so that its rising edge always occurs between data transitions and can be used to latch the output data externally. Figure 3 shows the timing operation of the AD9381. tPER tDCYCLE tSKEW DATACK DATA HSOUT Figure 3. Output Timing VSYNC FILTER AND ODD/EVEN FIELDS The VSYNC filter eliminates spurious VSYNCs, maintains a consistent timing relationship between the VSYNC and HSYNC output signals, and generates the odd/even field output. The filter works by examining the placement of VSYNC with respect to HSYNC and, if necessary, slightly shifting it in time at the VSOUT output. The goal is to keep the VSYNC and HSYNC leading edges from switching at the same time, eliminating confusion as to when the first line of a frame occurs. Enabling the VSYNC filter is done with Register 0x21[5]. Use of the VSYNC filter is recommended for all cases, including interlaced video, and is required when using the HSYNC per VSYNC counter. Figure 4 and Figure 5 illustrate even/odd field determination in two situations. FIELD 1 FIELD 0 SYNC SEPARATOR THRESHOLD FIELD 1 FIELD 0 23 2 1 4 31 HSIN VSIN 4 VSOUT O/E FIELD EVEN FIELD QUADRANT Figure 4. FIELD 1 FIELD 0 SYNC SEPARATOR THRESHOLD FIELD 1 FIELD 0 23 2 1 44 31 HSIN VSIN VSYOUT O/E FIELD ODD FIELD QUADRANT Figure 5. VSYNC Filter—Odd/Even HDMI RECEIVER The HDMI receiver section of the AD9381 allows the reception of a digital video stream, which is backward compatible with DVI and able to accommodate not only video of various for- mats (RGB, YCrCb 4:4:4, 4:2:2), but also up to eight channels of audio. Infoframes are transmitted carrying information about the video format, audio clocks, and many other items necessary for a monitor to use fully the information stream available. The earlier digital visual interface (DVI) format was restricted to an RGB 24-bit color space only. Embedded in this data stream were HSYNCs, VSYNCs, and display enable (DE) signals, but no audio information. The HDMI specification allows transmission of all the DVI capabilities, but adds several YCrCb formats that make the inclusion of a programmable color space converter (CSC) a very desirable feature. With this, the scaler following the AD9381 can specify that it always wishes to receive a particular format—for instance, 4:2:2 YCrCb—regardless of the transmitted mode. If RGB is sent, the CSC can easily convert that to 4:2:2 YCrCb while relieving the scaler of this task. In addition, the HDMI specification supports the transmission of up to eight channels of S/PDIF or I2S audio. The audio information is packetized and transmitted during the video blanking periods along with specific information about the clock frequency. Part of this audio information (audio Infoframe) tells the user how many channels of audio are being transmitted, where they should be placed, information regarding the source (make, model), and other data. DE GENERATOR The AD9381 has an onboard generator for DE, for start of active video (SAV) and for end of active video (EAV), all of which is necessary for describing the complete data stream for a BT656-compatible output. In addition to this particular output, it is possible to generate the DE for cases in which a scaler is not used. This signal alerts the following circuitry as to which are displayable video pixels. |
类似零件编号 - AD9381 |
|
类似说明 - AD9381 |
|
|
链接网址 |
| 隐私政策 |
| ALLDATASHEETCN.COM |
| ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Chinese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
