SNAU291A October   2023  – September 2024

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  7. 2EVM Quick Start
    1. 2.1 Hardware Setup
    2. 2.2 Software Setup
      1. 2.2.1 TICS Pro GUI Setup
      2. 2.2.2 Power Up Sequence
    3. 2.3 EVM Measurements
  8. 3Hardware
    1. 3.1 Device Operation Modes
    2. 3.2 EVM Configuration
      1. 3.2.1 Power Supply
      2. 3.2.2 Logic Input and Outputs
      3. 3.2.3 Clock Input
      4. 3.2.4 Clock Outputs
      5. 3.2.5 Status Outputs, LEDs and Test Points
  9. 4Software
    1. 4.1 TICS Pro LMKDB1108 Software
      1. 4.1.1 Input
        1. 4.1.1.1 Input Interface Type
        2. 4.1.1.2 Input Termination
        3. 4.1.1.3 Auto Output Disable (AOD)
        4. 4.1.1.4 LOS Event
        5. 4.1.1.5 LOS Readback
      2. 4.1.2 Device Info and EVM Setup
        1. 4.1.2.1 Device Info
        2. 4.1.2.2 EVM Setup
        3. 4.1.2.3 SMBus
      3. 4.1.3 Output
        1. 4.1.3.1 SMBus
          1. 4.1.3.1.1 Programmable Output Slew Rate Control
        2. 4.1.3.2 OE# Pin Control
        3. 4.1.3.3 Side Band Interface (SBI)
  10. 5Implementation Results
    1. 5.1 Typical Phase Noise Characteristic
  11. 6Hardware Design Files
    1. 6.1 Schematics
    2. 6.2 PCB Layouts
    3. 6.3 Bill of Materials (BOM)
  12. 7Compliance Information
    1. 7.1 Compliance and Certifications
  13. 8References
  14. 9Revision History
Programmable Output Slew Rate Control

The LMKDB1108 has 16 different slew rates options that can be assigned to the outputs. 0x0 is the fastest slew rate setting and 0xF is the slowest slew rate setting. To set the slew rate of each output, follow these steps:

  1. There are four different registers, SLEWRATE_OPT#, that can store up to four different slew rates. Select your desired slew rates by assigning a value from 0x0 (fastest) to 0xF (slowest) to each SLEWRATE_OPT# register. The default values set to each SLEWRATE_OPT# register can be found in Table 4-3.
    1. For example, if you wanted the two fastest slew rates and the slowest slew rate, assign 0x0, 0x1, and 0xF to registers SLEWRATE_OPT#. SLEWRATE_OPT1 = 0x0 (fastest), SLEWRATE_OPT2 = 0x1 (second fastest), SLEWRATE_OPT3 = 0xF (slowest), and SLEWRATE_OPT4 = 0xF (slowest) as shown in Figure 4-4.
      LMKDB1108EVM SLEWRATE_OPT#
                                    Assignment Example in TICS Pro Figure 4-4 SLEWRATE_OPT# Assignment Example in TICS Pro
    Table 4-3 Default SLEWRATE_OPT_# Values
    Register Field Name Default Value Default Slew Rate
    SLEWRATE_OPT_1 0x0 Fastest
    SLEWRATE_OPT_2 0x6 Fast (default for all outputs)
    SLEWRATE_OPT_3 0xA Slow
    SLEWRATE_OPT_4 0xF Slowest
  2. Set a slew rate for each output by using the drop-down menus under the Output Slew Rate Control Section. The default SLEWRATE_OPT# register assignment for all outputs is SLEWRATE_OPT2, which has a default of 0x6.
    1. Following the example from step 1a, if you wanted CLK0, CLK1, CLK2, and CLK3 to have the fastest slew rate, CLK4 and CLK7 to have the slowest slew rate, and CLK 5 and CLK6 to have the second fastest slew rate, set the drop-down menus of CLK0, CLK1, CLK2, and CLK3 to OPT_1, CLK4 and CLK7 to OPT_3 or OPT_4, and CLK5 and CLK6 to OPT_2 as shown in Figure 4-5.
      LMKDB1108EVM Setting Output
                                    Slew Rate Example in TICS Pro Figure 4-5 Setting Output Slew Rate Example in TICS Pro