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

7.4.2.1.2 SPI Read Transaction Format

A SPI read transaction is 34 bits per device and consists of two 17-bit frames. The first 17-bit read transaction frame shifts in the address to be read, followed by a dummy transaction second frame to shift out 17-bit read data. The R/W bit is 1'b for the read transaction, as shown in Figure 19.

The first 17 bits from the read transaction specifies 1-bit of R/W and 8-bits of address A7-A0 in the first 8 bits. The eight 1’s following the address are ignored. The second dummy transaction acts like a read operation on address 0xFF and needs to be ignored. However, the transaction is necessary in order to shift out the read data D7-D0 in the last 8 bits of the MISO output. As with the SPI Write, the “prime” values on MISO during the first 16 clocks are don’t-care for this portion of the transaction. The values shifted out on MISO during the last 17 clocks reflect the read address and 8-bit read data for the current transaction.

LMH1226 td04_signal_timing_spi_read_snls515.gifFigure 19. Signal Timing for a SPI Read Transaction