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

5 Pin Configuration and Functions

RTW Package
24-Pin QFN
Top View
LMH1226 pin_diagram_snls517.gif

Pin Functions

PIN I/O (1) DESCRIPTION
NAME NO.
High-Speed Differential I/Os
IN1+ 4 I, Analog Differential complementary inputs with internal 100-Ω termination. Requires external 4.7-µF AC coupling capacitors for SMPTE and 10 GbE.
IN1- 5 I, Analog
OUT0+ 18 O, Analog Differential complementary outputs with 100-Ω internal termination. Requires external 4.7-µF AC coupling capacitors. Output driver OUT0± can be disabled under user control.
OUT0- 17 O, Analog
OUT1+ 15 O, Analog Differential complementary outputs with 100 Ω internal termination. Requires external 4.7-µF AC coupling capacitors. Output driver OUT1± can be disabled under user control.
OUT1- 14 O, Analog
RSV1 1 Reserved pins.
Do not connect.
RSV2 2
Control Pins
LOCK_N 12 O, LVCMOS, OD LOCK_N is the reclocker lock indicator for the selected input. LOCK_N is pulled LOW when the reclocker has acquired locking condition. LOCK_N is an open drain output, 3.3 V tolerant, and requires an external 2-kΩ to 5-kΩ pull-up resistor to logic supply. LOCK_N pin can be re-configured to indicate INT_N (Interrupt) through register programming.
IN_OUT_SEL 8 I, 4-LEVEL IN_OUT_SEL selects the signal flow at input ports to output ports. See Table 2 for details. This pin setting can be overridden by register control.
OUT_CTRL 19 I, 4-LEVEL OUT_CTRL selects the signal flow from IN1± to OUT1± and OUT0±. It selects reclocked data, reclocked data and clock, bypassed reclocker data (equalized data to output driver), or bypassed equalizer and reclocker data. See Table 4 for details. This pin setting can be overridden by register control.
VOD_DE 11 I, 4-LEVEL VOD_DE selects the driver output amplitude and de-emphasis level for both OUT0± and OUT1±. See Table 5for details. This pin setting can be overridden by register control.
MODE_SEL 6 I, 4-LEVEL MODE_SEL enables SPI or SMBus serial control interface. See Table 6 for details.
Serial Control Interface (SPI Mode), MODE_SEL = F (Float)
SS_N 7 I, LVCMOS SS_N is the Slave Select. When SS_N is at logic Low, it enables SPI access to the LMH1226 slave device. SS_N is a LVCMOS input reference to VDDIO.
MISO 20 O, LVCMOS MISO is the SPI control serial data output from the LMH1226 slave device. MISO is a LVCMOS output reference to VDDIO.
MOSI 10 I, LVCMOS MOSI is used as the SPI control serial data input to the LMH1226 slave device. MOSI is LVCMOS input reference to VDDIO.
SCK 21 I, LVCMOS SCK is the SPI serial input clock to the LMH1226 slave device. SCK is LVCMOS reference to VDDIO.
Serial Control Interface (SMBus Mode) , MODE_SEL = L (1 kΩ to VSS)
ADDR0 7 Strap, 4-LEVEL ADDR[1:0] are SMBus address straps to select one of the 16 supported SMBus addresses. ADDR[1:0] are 4-level straps and are read into the device at power up.
ADDR1 20 Strap, 4-LEVEL
SDA 10 IO, LVCMOS, OD SDA is the SMBus bi-directional open drain SDA data line to or from the LMH1226 slave device. SDA is an open drain IO and tolerant to 3.3 V. SDA requires an external 2-kΩ to 5-kΩ pull-up resistor to the SMBus termination voltage.
SCL 21 I, LVCMOS, OD SCL is the SMBus input clock to the LMH1226 slave device. It is driven by a LVCMOS open drain driver from the SMBus master. SCL is tolerant to 3.3 V and requires an external 2-kΩ to 5-kΩ pull up resistor to the SMBus termination voltage.
Power
VSS 3, 9, 16 I, Ground Ground reference.
VIN 24 I, Power VIN is connected to an external power supply. It accepts either 2.5 V ± 5% or 1.8 V ± 5%. When VIN is powered from 2.5 V, VDD_LDO is the output of an on-chip LDO regulator. For lower power operation, both VIN and VDD_LDO should be connected to a 1.8 V supply.
VDDIO 22 I, Power VDDIO powers the LVCMOS IO and 4-level input logic and connects to 2.5 V ± 5% supply.
VDD_LDO 23 IO, Power VDD_LDO is the output of the internal 1.8 V LDO regulator when VIN is connected to a 2.5 V supply. VDD_LDO output requires external 1-μF and 0.1-μF bypass capacitors to VSS. The internal LDO is designed to power internal circuitry only. VDD_LDO is an input when VIN is powered from 1.8 V for lower power operation. When VIN is connected to a 1.8 V supply, both VIN and VDD_LDO should be connected to a 1.8 V supply.
VDD_CDR 13 I, Power VDD_CDR powers the reclocker circuitry and connects to 2.5 V ± 5% supply.
EP I, Ground EP is the exposed pad at the bottom of the QFN package. The exposed pad must be connected to the ground plane through a via array. See Figure 29 for details.
(1) I = Input, O = Output, IO = Input or Output, OD = Open Drain, LVCMOS = 2-State Logic, 4-LEVEL = 4-State Logic