JAJSDN8C March   2017  – April 2019 LMX2594

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      概略回路図
  4. 改訂履歴
  5. 概要(続き)
  6. Pin Configuration and Functions
    1.     Pin Functions
  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. 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. 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

パッケージ・オプション

メカニカル・データ(パッケージ|ピン)
サーマルパッド・メカニカル・データ
発注情報

N-Divider and Fractional Circuitry

The N-divider includes fractional compensation and can achieve any fractional denominator from 1 to (232 – 1). The integer portion of N is the whole part of the N-divider value, and the fractional portion, Nfrac = NUM / DEN, is the remaining fraction. In general, the total N-divider value is determined by N + NUM / DEN. The N, NUM and DEN are software programmable. The higher the denominator, the finer the resolution step of the output. For example, even when using fPD = 200 MHz, the output can increment in steps of 200 MHz / (232 – 1) = 0.047 Hz.Equation 2 shows the relationship between the phase detector and VCO frequencies. Note that in SYNC mode, there is an extra divider that is not shown in Equation 2.

Equation 2. LMX2594 eq2_snas696.gif

The sigma-delta modulator that controls this fractional division is also programmable from integer mode to fourth order. To make the fractional spurs consistent, the modulator is reset any time that the R0 register is programmed.

The N-divider has minimum value restrictions based on the modulator order and VCO frequency. Furthermore, the PFD_DLY_SEL bit must be programmed in accordance to the Table 2.

Table 2. Minimum N-Divider Restrictions

MASH_ORDER fVCO (MHz) MINIMUM N PFD_DLY_SEL
0 ≤ 12500 28 1
> 12500 32 2
1 ≤ 10000 28 1
10000-12500 32 2
>12250 36 3
2 ≤ 10000 32 2
>10000 36 3
3 ≤ 10000 36 3
>10000 40 4
4 ≤ 10000 44 5
>10000 48 6