JAJSDN8C March   2017  – April 2019 LMX2594

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      概略回路図
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Reference Oscillator Input
      2. 8.3.2  Reference Path
        1. 8.3.2.1 OSCin Doubler (OSC_2X)
        2. 8.3.2.2 Pre-R Divider (PLL_R_PRE)
        3. 8.3.2.3 Programmable Multiplier (MULT)
        4. 8.3.2.4 Post-R Divider (PLL_R)
        5. 8.3.2.5 State Machine Clock
      3. 8.3.3  PLL Phase Detector and Charge Pump
      4. 8.3.4  N-Divider and Fractional Circuitry
      5. 8.3.5  MUXout Pin
        1. 8.3.5.1 Lock Detect
        2. 8.3.5.2 Readback
      6. 8.3.6  VCO (Voltage-Controlled Oscillator)
        1. 8.3.6.1 VCO Calibration
        2. 8.3.6.2 Determining the VCO Gain
      7. 8.3.7  Channel Divider
      8. 8.3.8  Output Buffer
      9. 8.3.9  Power-Down Modes
      10. 8.3.10 Phase Synchronization
        1. 8.3.10.1 General Concept
        2. 8.3.10.2 Categories of Applications for SYNC
        3. 8.3.10.3 Procedure for Using SYNC
        4. 8.3.10.4 SYNC Input Pin
      11. 8.3.11 Phase Adjust
      12. 8.3.12 Fine Adjustments for Phase Adjust and Phase SYNC
      13. 8.3.13 Ramping Function
        1. 8.3.13.1 Manual Pin Ramping
          1. 8.3.13.1.1 Manual Pin Ramping Example
        2. 8.3.13.2 Automatic Ramping
          1. 8.3.13.2.1 Automatic Ramping Example (Triangle Wave)
      14. 8.3.14 SYSREF
        1. 8.3.14.1 Programmable Fields
        2. 8.3.14.2 Input and Output Pin Formats
          1. 8.3.14.2.1 Input Format for SYNC and SysRefReq Pins
          2. 8.3.14.2.2 SYSREF Output Format
        3. 8.3.14.3 Examples
        4. 8.3.14.4 SYSREF Procedure
      15. 8.3.15 SysRefReq Pin
    4. 8.4 Device Functional Modes
    5. 8.5 Programming
      1. 8.5.1 Recommended Initial Power-Up Sequence
      2. 8.5.2 Recommended Sequence for Changing Frequencies
      3. 8.5.3 General Programming Requirements
    6. 8.6 Register Maps
      1. 8.6.1  General Registers R0, R1, & R7
        1. Table 24. Field Descriptions
      2. 8.6.2  Input Path Registers
        1. Table 25. Field Descriptions
      3. 8.6.3  Charge Pump Registers (R13, R14)
        1. Table 26. Field Descriptions
      4. 8.6.4  VCO Calibration Registers
        1. Table 27. Field Descriptions
      5. 8.6.5  N Divider, MASH, and Output Registers
        1. Table 28. Field Descriptions
      6. 8.6.6  SYNC and SysRefReq Input Pin Register
        1. Table 29. Field Descriptions
      7. 8.6.7  Lock Detect Registers
        1. Table 30. Field Descriptions
      8. 8.6.8  MASH_RESET
        1. Table 31. Field Descriptions
      9. 8.6.9  SysREF Registers
        1. Table 32. Field Descriptions
      10. 8.6.10 CHANNEL Divider Registers
        1. Table 33. Field Descriptions
      11. 8.6.11 Ramping and Calibration Fields
        1. Table 34. Field Descriptions
      12. 8.6.12 Ramping Registers
        1. 8.6.12.1 Ramp Limits
          1. Table 35. Field Descriptions
        2. 8.6.12.2 Ramping Triggers, Burst Mode, and RAMP0_RST
          1. Table 36. Field Descriptions
        3. 8.6.12.3 Ramping Configuration
          1. Table 37. Field Descriptions
      13. 8.6.13 Readback Registers
        1. Table 38. Field Descriptions
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 OSCin Configuration
      2. 9.1.2 OSCin Slew Rate
      3. 9.1.3 RF Output Buffer Power Control
      4. 9.1.4 RF Output Buffer Pullup
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 デバイス・サポート
      1. 12.1.1 デベロッパー・ネットワークの製品に関する免責事項
      2. 12.1.2 開発サポート
    2. 12.2 ドキュメントのサポート
      1. 12.2.1 関連資料
    3. 12.3 ドキュメントの更新通知を受け取る方法
    4. 12.4 コミュニティ・リソース
    5. 12.5 商標
    6. 12.6 静電気放電に関する注意事項
    7. 12.7 Glossary
  13. 13メカニカル、パッケージ、および注文情報

8.3.13.2.1 Automatic Ramping Example (Triangle Wave)

Suppose user wants to generate a sawtooth ramp that goes from 8 to 10 GHz in 2 ms (including calibration breaks) with a phase-detector frequency of 50 MHz. Divide this into segments of 50 MHz where the VCO ramps for 25 µs, then calibrates for 25 µs, for a total of 50 µs. There would therefore be 40 such segments which span over a 2-GHz range and would take 2 ms, including calibration time.

Table 17. Sawtooth Ramping Example

FIELD PROGRAMMING DESCRIPTION
RAMP_EN 1 = Enabled
RAMP_MANUAL 0 = Automatic ramping mode
RAMP_TRIG_CAL 0 = Disabled
RAMP_THRESH 16777216 (= 50-MHz ramp_thresh) 50 MHz / 50 MHz × 224 = 16777216
RAMP_DLY 0 = 1 clock cycle
RAMPx_LEN 50000 1000 µs × 50 MHz = 50000
RAMP0_INC 13422 (2000 MHz) / (50 MHz) × 224 / 50000 = 13422
RAMP1_INC 1073728402 (–2000 MHz) / (50 MHz) × 224 / 50000 = –13422
2’s complement = 230 – 13422 = 1073728402
RAMP0_NEXT 1 = RAMP1
RAMP1_NEXT 0 = RAMP0
RAMPx_NEXT_TRIG 0 = Timeout counter
RAMP_TRIG_x 0 = Disabled
RAMP0_RST 1 = Enabled Not necessary, but good practice to reset.
RAMP1_RST 0 = Disabled Do not reset this, or ramp does not work.
RAMP_BURST_COUNT 0
RAMP_BURST_TRIG 0 = Ramp Transition

NOTE

To calculate ramp_scale_count and ramp_dly_cnt, remember that the desired calibration time is 25 µs.
LMX2594 Auto_Ramping_Ex1_snas696_v2.gifFigure 29. Triangle Waveform Example