SNAS736C June   2017  – April 2019 LMX2595

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  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 Timing Requirements
    7. 6.7 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  Reference Oscillator Input
      2. 7.3.2  Reference Path
        1. 7.3.2.1 OSCin Doubler (OSC_2X)
        2. 7.3.2.2 Pre-R Divider (PLL_R_PRE)
        3. 7.3.2.3 Programmable Multiplier (MULT)
        4. 7.3.2.4 Post-R Divider (PLL_R)
        5. 7.3.2.5 State Machine Clock
      3. 7.3.3  PLL Phase Detector and Charge Pump
      4. 7.3.4  N-Divider and Fractional Circuitry
      5. 7.3.5  MUXout Pin
        1. 7.3.5.1 Lock Detect
        2. 7.3.5.2 Readback
      6. 7.3.6  VCO (Voltage-Controlled Oscillator)
        1. 7.3.6.1 VCO Calibration
        2. 7.3.6.2 Determining the VCO Gain
      7. 7.3.7  Channel Divider
      8. 7.3.8  VCO Doubler
      9. 7.3.9  Output Buffer
      10. 7.3.10 Power-Down Modes
      11. 7.3.11 Phase Synchronization
        1. 7.3.11.1 General Concept
        2. 7.3.11.2 Categories of Applications for SYNC
        3. 7.3.11.3 Procedure for Using SYNC
        4. 7.3.11.4 SYNC Input Pin
      12. 7.3.12 Phase Adjust
      13. 7.3.13 Fine Adjustments for Phase Adjust and Phase SYNC
      14. 7.3.14 Ramping Function
        1. 7.3.14.1 Manual Pin Ramping
          1. 7.3.14.1.1 Manual Pin Ramping Example
        2. 7.3.14.2 Automatic Ramping
          1. 7.3.14.2.1 Automatic Ramping Example (Triangle Wave)
      15. 7.3.15 SYSREF
        1. 7.3.15.1 Programmable Fields
        2. 7.3.15.2 Input and Output Pin Formats
          1. 7.3.15.2.1 Input Format for SYNC and SysRefReq Pins
          2. 7.3.15.2.2 SYSREF Output Format
        3. 7.3.15.3 Examples
        4. 7.3.15.4 SYSREF Procedure
      16. 7.3.16 SysRefReq Pin
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 Recommended Initial Power-Up Sequence
      2. 7.5.2 Recommended Sequence for Changing Frequencies
      3. 7.5.3 General Programming Requirements
    6. 7.6 Register Maps
      1. 7.6.1  General Registers R0, R1, & R7
        1. Table 25. Field Descriptions
      2. 7.6.2  Input Path Registers
        1. Table 26. Field Descriptions
      3. 7.6.3  Charge Pump Registers (R13, R14)
        1. Table 27. Field Descriptions
      4. 7.6.4  VCO Calibration Registers
        1. Table 28. Field Descriptions
      5. 7.6.5  N Divider, MASH, and Output Registers
        1. Table 29. Field Descriptions
      6. 7.6.6  SYNC and SysRefReq Input Pin Register
        1. Table 30. Field Descriptions
      7. 7.6.7  Lock Detect Registers
        1. Table 31. Field Descriptions
      8. 7.6.8  MASH_RESET
        1. Table 32. Field Descriptions
      9. 7.6.9  SysREF Registers
        1. Table 33. Field Descriptions
      10. 7.6.10 CHANNEL Divider And VCO Doubler Registers
        1. Table 34. Field Descriptions
      11. 7.6.11 Ramping and Calibration Fields
        1. Table 35. Field Descriptions
      12. 7.6.12 Ramping Registers
        1. 7.6.12.1 Ramp Limits
          1. Table 36. Field Descriptions
        2. 7.6.12.2 Ramping Triggers, Burst Mode, and RAMP0_RST
          1. Table 37. Field Descriptions
        3. 7.6.12.3 Ramping Configuration
          1. Table 38. Field Descriptions
      13. 7.6.13 Readback Registers
        1. Table 39. Field Descriptions
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 OSCin Configuration
      2. 8.1.2 OSCin Slew Rate
      3. 8.1.3 RF Output Buffer Power Control
      4. 8.1.4 RF Output Buffer Pullup
      5. 8.1.5 Performance Comparison Between 1572 (0x0624) and 3115 (0x0C2B) for Register DBLR_IBIAS_CTRL1 (R25[15:0])
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.4 Device Functional Modes

Although there are a vast number of ways to configure this device, only one is really functional.

Table 22. Device Functional Modes

MODE DESCRIPTION SOFTWARE SETTINGS
RESET Registers are held in their reset state. This device does have a power on reset, but it is good practice to also do a software reset if there is any possibility of noise on the programming lines, especially if there is sharing with other devices. Also realize that there are registers not disclosed in the data sheet that are reset as well. RESET = 1, POWERDOWN = 0
POWERDOWN Device is powered down. POWERDOWN = 1
or CE Pin = Low
Normal operating mode This is used with at least one output on as a frequency synthesizer.
SYNC mode This is used where part of the channel divider is in the feedback path to ensure deterministic phase. VCO_PHASE_SYNC = 1
SYSREF mode In this mode, RFoutB is used to generate pulses for SYSREF. VCO_PHASE_SYNC =1, SYSREF_EN = 1