SLVSES8A October   2020  – December 2020 LM5127-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Pin Configuration and 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 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Device Enable (EN, VCC_HOLD)
      2. 8.3.2  Dual Input VCC Regulator (BIAS, VCCX, VCC)
      3. 8.3.3  Dual Input VDD Switch (VDD, VDDX)
      4. 8.3.4  Device Configuration and Light Load Switching Mode Selection (CFG/MODE)
      5. 8.3.5  Fixed or Adjustable Output Regulation Target (VOUT, FB)
      6. 8.3.6  Overvoltage Protection (VOUT, FB)
      7. 8.3.7  Power Good Indicator (PGOOD)
      8. 8.3.8  Programmable Switching Frequency (RT)
      9. 8.3.9  External Clock Synchronization (SYNC)
      10. 8.3.10 Programmable Spread Spectrum (DITHER)
      11. 8.3.11 Programmable Soft Start (SS)
      12. 8.3.12 Fast Re-start using VCC_HOLD (VCC_HOLD)
      13. 8.3.13 Transconductance Error Amplifier and PWM (COMP)
      14. 8.3.14 Current Sensing and Slope Compensation (CSA, CSB)
      15. 8.3.15 Constant Peak Current Limit (CSA, CSB)
      16. 8.3.16 Maximum Duty Cycle and Minimum Controllable On-time Limits (Boost)
      17. 8.3.17 Bypass Mode (Boost)
      18. 8.3.18 Minimum Controllable On-time and Minimum Controllable Off-time Limits (Buck)
      19. 8.3.19 Low Dropout Mode for Extended Minimum Input Voltage (Buck)
      20. 8.3.20 Programmable Hiccup Mode Overload Protection (RES)
      21. 8.3.21 MOSFET Drivers and Hiccup Mode Fault Protection (LO, HO, HB)
      22. 8.3.22 Battery Monitor (BMOUT, BMIN_FIX, BMIN_PRG)
      23. 8.3.23 Dual-phase Interleaved Configuration for High Current Supply (CFG)
      24. 8.3.24 Thermal Shutdown Protection
      25. 8.3.25 External VCCX Supply Reduces Power Dissipation
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Status
        1. 8.4.1.1 Shutdown Mode
        2. 8.4.1.2 Configuration Mode
        3. 8.4.1.3 Active Mode
        4. 8.4.1.4 Sleep Mode
        5. 8.4.1.5 Deep Sleep Mode
          1. 8.4.1.5.1 Cutting Leakage Path in Deep Sleep Mode (DIS, SLEEP1, SENSE1)
        6. 8.4.1.6 VCC HOLD Mode
      2. 8.4.2 Light Load Switching Mode
        1. 8.4.2.1 Forced PWM (FPWM) Operation
        2. 8.4.2.2 Diode Emulation (DE) Operation (Connect RSS at SS)
        3. 8.4.2.3 Forced Diode Emulation Operation in FPWM Mode
        4. 8.4.2.4 Skip Mode Operation
      3. 8.4.3 LM5127 Cheat Sheet
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Recommended Power Tree Architecture
        2. 9.2.2.2 Application Ideas
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

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

Recommended Power Tree Architecture

  • It is strongly recommended to have at least one fixed 5-V rail and connect the 5 V output to the VCCX pin.
  • If battery monitor is required, configure CH1 buck.
  • If 3.3-V rail is required, program the VOUT3 to the fixed 3.3 V and utilize the VDDX function.
  • SEPIC configuration is good when the load current is less than about 3 - 4 A. In the SEPIC configuration, the maximum input voltage has to be limited below 42 V - VVOUT1 since the SW node voltage is VSUPPLY plus VLOAD in the SEPIC configuration and switching noise should be considered.
  • The maximum load current of the single buck channel can be up to about 20 A with proper thermal management.
  • The maximum load current of the dual-phase buck can be up to about 40 A with proper thermal management.
  • Cascaded configuration is allowed.
  • The BIAS pin should be connected to the highest voltage rail in the system because the internal charge pump creates BIAS + 5 V rail for HB1. Especially, the BIAS pin should be connected to the output of the boost converter in boost configuration.
  • Populate 100 pF CSS if CH1 is used as a pre-boost.
  • The CH2 buck input voltage can be higher or lower than the CH3 buck input voltage, but the BIAS pin should be always connected to the highest potential input voltage.