SNLS534D April   2016  – June 2018 LMH1226

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Block Diagram
  4. 4 Revision History
  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 AC Timing Specifications
    7. 6.7 Serial Parallel Interface (SPI) AC 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 Configuration Pins
      2. 7.3.2 Input Carrier Detect
      3. 7.3.3 Continuous Time Linear Equalizer (CTLE)
        1. 7.3.3.1 Adaptive PCB Trace Equalizer (IN1±)
      4. 7.3.4 Input-Output Mux Selection
      5. 7.3.5 Clock and Data Recovery (CDR) Reclocker
      6. 7.3.6 Internal Eye Opening Monitor (EOM)
      7. 7.3.7 Output Function Control
      8. 7.3.8 Output Driver Amplitude and De-Emphasis Control
      9. 7.3.9 Status Indicators and Interrupts
        1. 7.3.9.1 LOCK_N (Lock Indicator)
        2. 7.3.9.2 CD_N (Carrier 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 Transactions
          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
          1. 7.4.2.1.1 SPI Write Transaction Format
          2. 7.4.2.1.2 SPI Read Transaction Format
        2. 7.4.2.2 SPI Daisy Chain
    5. 7.5 LMH1226 Register Map
      1. 7.5.1 Share Register Page
      2. 7.5.2 CTLE/CDR Register Page
      3. 7.5.3 Drivers Register Page
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 General Guidance for SMPTE and 10 GbE Applications
      2. 8.1.2 LMH1219 and LMH1226 Compatibility
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Recommended VOD and DEM Register Settings
      4. 8.2.4 Application Performance Plots
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 PCB Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.1 4-Level Input Configuration Pins

The 4-level input configuration pins use a resistor divider to provide four logic states for each control pin. There is an internal 30-kΩ pull-up and a 60-kΩ pull-down connected to the control pin that sets the default voltage at 2/3 x VDDIO. These resistors, together with the external resistor, combine to achieve the desired voltage level. By using the 1-kΩ pull-down, 20-kΩ pull-down, no connect, and 1-kΩ pull-up, the optimal voltage levels for each of the four input states are achieved as shown in Table 1.

Table 1. 4-Level Control Pin Settings

LEVEL SETTING RESULTING PIN VOLTAGE
H Tie 1 kΩ to VDDIO VDDIO
F Float (leave pin open) 2/3 × VDDIO
R Tie 20 kΩ to VSS 1/3 × VDDIO
L Tie 1 kΩ to VSS 0

Typical 4-Level Input Thresholds:

  • Internal Threshold between L and R = 0.2 × VDDIO
  • Internal Threshold between R and F = 0.5 × VDDIO
  • Internal Threshold between F and H = 0.8 × VDDIO