ZHCSKF4C March   2017  – October 2019 LMH1228

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     简化方框图
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Recommended SMBus Interface Timing Specifications
    7. 6.7 Serial Parallel Interface (SPI) Timing Specifications
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 4-Level Input Pins and Thresholds
      2. 7.3.2 OUT0_SEL and SDI_OUT2_SEL Control
      3. 7.3.3 Input Signal Detect
      4. 7.3.4 Continuous Time Linear Equalizer (CTLE)
      5. 7.3.5 Clock and Data (CDR) Recovery
      6. 7.3.6 Internal Eye Opening Monitor (EOM)
      7. 7.3.7 Output Function Control
      8. 7.3.8 Output Driver Control
        1. 7.3.8.1 Line-Side Output Cable Driver (SDI_OUT1+, SDI_OUT2+)
          1. 7.3.8.1.1 Output Amplitude (VOD)
          2. 7.3.8.1.2 Output Pre-Emphasis
          3. 7.3.8.1.3 Output Slew Rate
          4. 7.3.8.1.4 Output Polarity Inversion
        2. 7.3.8.2 Host-Side 100-Ω Output Driver (OUT0±)
      9. 7.3.9 Status Indicators and Interrupts
        1. 7.3.9.1 LOCK_N (Lock Indicator)
        2. 7.3.9.2 SD_N (Signal Detect)
        3. 7.3.9.3 INT_N (Interrupt)
    4. 7.4 Device Functional Modes
      1. 7.4.1 System Management Bus (SMBus) Mode
        1. 7.4.1.1 SMBus Read and Write Transaction
          1. 7.4.1.1.1 SMBus Write Operation Format
          2. 7.4.1.1.2 SMBus Read Operation Format
      2. 7.4.2 Serial Peripheral Interface (SPI) Mode
        1. 7.4.2.1 SPI Read and Write Transactions
        2. 7.4.2.2 SPI Write Transaction Format
        3. 7.4.2.3 SPI Read Transaction Format
        4. 7.4.2.4 SPI Daisy Chain
    5. 7.5 Register Maps
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 SMPTE Requirements and Specifications
      2. 8.1.2 Low-Power Optimization
      3. 8.1.3 Optimized Loop Bandwidth Settings for Arria 10 FPGA Applications
    2. 8.2 Typical Applications
      1. 8.2.1 Dual Cable Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Distribution Amplifier
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Stack-Up and Ground References
      2. 10.1.2 High-Speed PCB Trace Routing and Coupling
        1. 10.1.2.1 SDI_OUT1± and SDI_OUT2±:
        2. 10.1.2.2 IN0± and OUT0±:
      3. 10.1.3 Anti-Pads
      4. 10.1.4 BNC Connector Layout and Routing
      5. 10.1.5 Power Supply and Ground Connections
      6. 10.1.6 Footprint Recommendations
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 相关文档
    2. 11.2 接收文档更新通知
    3. 11.3 支持资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 出口管制提示
    7. 11.7 Glossary
  12. 12机械、封装和可订购信息
    1. 12.1 Package Option Addendum
      1. 12.1.1 Packaging Information
      2. 12.1.2 Tape and Reel Information

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

7.3.3 Input Signal Detect

IN0 has a signal detect circuit to monitor the presence or absence of an input signal. When the input signal amplitude for the selected input exceeds the signal detect assert threshold, the LMH1228 operates in normal operation mode.

In the absence of an input signal, the LMH1228 automatically goes into Power Save Mode to conserve power dissipation. When a valid signal is detected, the LMH1228 automatically exits Power Save Mode and returns to the normal operation mode. If the ENABLE pin is pulled low, the LMH1228 is forced into Power-Down Mode. In Power Save Mode, both the signal detect circuit and the serial interface remain active. In Power-Down Mode, only the serial interface remains active.

Users can monitor the status of the signal detect through register programming. This can be done either by configuring the LOCK_N pin to output the SD_N status or by monitoring the signal detect status register.

Table 3. Input Signal Detect Modes of Operation

ENABLE SIGNAL INPUT OPERATING MODE
H 100-Ω signal input at IN0± Normal operation
Signal Detector at IN0±
Serial interface active
H No signal at IN0± Power Save Mode
Signal Detector at IN0±
Serial interface active
L Input signal ignored Power-Down Mode
Forced device power down
Serial interface active