原标题：TI LMH1218低功耗视频电缆驱动解决方案

　　TI公司的LMH1218是集成了reclocker的低功耗视频电缆驱动器,驱动和SMPTE-SDI, SMPTE 2022-5/6, 10GbE以太网和DVB-ASI标准兼容的视频数据,支持11.88Gbps速率,适用于超高清视频4K/8K应用,单电源2.5V工作,主要用在UHDTV/4K/8K/HDTV/SDTV视频, 数字视频路由器和交换, 数字视频处理和编辑, DVB-ASI和分布放大器, SMPTE 2022-5/6 10GbE以太网.本文介绍了LMH1218主要特性,功能框图, SPI模式和SMBus模式配置图以及评估板LMH1218EVM主要特性,电路图,材料清单和PCB布局图.

　　The LMH1218 is a low-power cable driver with integrated reclocker to drive serial video data compatible to SMPTE-SDI, SMPTE 2022-5/6, 10GbE Ethernet, and DVB-ASI standards. The LMH1218 supports up to 11.88 Gbps to enable Ultra High Definition Video for 4K/8K applications. With 75-Ω and 50-Ω transmitter outputs, the LMH1218 enables multiple media options such as coax, fiber, and FR-4 PCB.

　　The integrated 2-to-1 MUX on the input of the LMH1218 enables selection between two video sources, while the programmable equalizer compensates for the PC board loss to extend signal reach. With a wide range clock-and-data recovery (CDR) circuit, the on-chip reclocker automatically detects and locks to serial data from 270 Mbps to 11.88 Gbps without the need for an external reference clock and loop filter component, thereby simplifying board design and lowering system cost. The reclocked serial data can be routed to either the 75-Ω or 50-Ω transmitter output, or both simultaneously (1-to-2 fanout mode). The output voltage swing is compatible to SFF-8431 (SFP+), ST-2082/1 (Proposed), SMPTE 424M, 344M, 292M, and 259M standards.

　　A non-disruptive eye monitor allows for real-time measurement of serial data to simplify system startup or field tuning. The LMH1218 can be programmed using SPI or SMBus Interface.

　　LMH1218主要特性:

　　Supports ST-2082 (Proposed), ST-2081 Proposed), SMPTE 424M, 344M, 292M, 259M, DVB-ASI, SFF-8431 (SFP+) and 10GbE Ethernet for SMPTE 2022-5/6

　　Locks to rates 11.88 Gbps, 5.94 Gbps, 2.97 Gbps, 1.485 Gbps, or Divided by 1.001 sub-rates, DVB- ASI (270 Mbps) and 10GbE (10.3125 Gbps)

　　Reference-free Operation with Fast Lock Time Covering All Supported or Selected Data Rates

　　75-Ω and 100-Ω Transmitter Outputs

　　Integrated 2:1 Mux Input, 1:2 Demux/Fanout Outputs

　　Automatic Slew Rate Based on Input Rate Detect

　　On-chip Eye Monitor

　　Low 300 mW Power Consumption With Automatic Power Down On Loss Of Input Signal

　　Programmable via SPI, Or SMBus Interface

　　Single 2.5-V Supply Operation

　　Small 4 mm × 4 mm 24-pin QFN Package

　　–40℃ to +85℃ Operating Temperature Range

　　LMH1218应用:

　　UHDTV/4K/8K/HDTV/SDTV Video

　　Digital Video Routers and Switches

　　Digital Video Processing and Editing

　　DVB-ASI and Distribution Amplifiers

　　10GbE for SMPTE 2022-5/6

　　图1. LMH1218框图

　　图2. LMH1218 SPI模式配置图

　　图3. LMH1218 SMBus模式配置图

　　评估板LMH1218EVM

　　The LMH1218EVM evaluation module provides a complete high bandwidth platform to evaluate the SDI/UHD and 10 GbE signal conditioning features of the Texas Instruments LMH1218 UHD Cable Driver with Integrated Reclocker. The LMH1218EVM can be used for standard compliance testing, performance evaluation, and initial system prototyping. The SMA and BNC edge launch connectors used for the LMH1218EVM will interface to multiple system connector types via commercially available breakout cables, adaptors, and boards (not included). This flexible connectivity enables integrated system level testing between TI’s 12G SDI Cable Driver with Reclocker and 3rd party ASIC/FPGA host boards. A graphical user interface can be used to manage LMH1218 device registers.

　　图4. 评估板LMH1218EVM外形图

　　评估板LMH1218EVM主要特性:

　　• Locks to standard SDI (2.97 Gbps, 1.485 Gbps, or divide-by-1.001 sub-rates), DVB-ASI (270 Mbps), ST-2081 (5.94 Gbps proposed), ST-2082 (11.88 Gbps proposed), and 10 GbE data rates

　　• Integrated 2:1 100 Ω mux on input and 1:2 fan-out (one 75 Ω and one 100 Ω) output drivers with deemphasis supporting dual media (coax and fiber)

　　• Programmable by SPI or SMBus interface

　　• 100 Ω differential and 75 Ω single-ended output drivers with de-emphasis

　　• Single supply operation: VDD = 2.5 V ± 5%

　　• High speed signal flow–thru pin-out package: 24-pin QFN (4 mm x 4 mm, 0.5 mm pitch)

　　• GUI platform to support fast bring-up during product development

　　• -40℃ to +85℃ Operation

　　评估板LMH1218EVM应用:

　　• UHDTV/4K/8K/HDTV/SDTV Video

　　• Digital Video Routers and Switches

　　• Digital Video Processing and Editing

　　• DVB-ASI

　　• Distribution Amplifiers

　　评估板LMH1218EVM材料清单: