JAJSJE8A May   2021  – March 2022 TPS25830A-Q1 , TPS25832A-Q1

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 概要 (続き)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Switching Characteristics
    8. 8.8 Typical Characteristics
  9. 9 Parameter Measurement Information
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1  Buck Regulator
      2. 10.3.2  Enable/UVLO and Start-Up
      3. 10.3.3  Switching Frequency and Synchronization (RT/SYNC)
      4. 10.3.4  Spread-Spectrum Operation
      5. 10.3.5  VCC, VCC_UVLO
      6. 10.3.6  Minimum ON-Time, Minimum OFF-Time
      7. 10.3.7  Internal Compensation
      8. 10.3.8  Bootstrap Voltage (BOOT)
      9. 10.3.9  RSNS, RSET, RILIMIT and RIMON
      10. 10.3.10 Overcurrent and Short Circuit Protection
        1. 10.3.10.1 Current Limit Setting using RILIMIT
        2. 10.3.10.2 Current Limit Setting for MFI OCP
        3. 10.3.10.3 Buck Average Current Limit Design Example
        4. 10.3.10.4 External MOSFET Gate Drivers
        5. 10.3.10.5 Cycle-by-Cycle Buck Current Limit
      11. 10.3.11 Overvoltage, IEC and Short to Battery Protection
        1. 10.3.11.1 VBUS and VCSN/OUT Overvoltage Protection
        2. 10.3.11.2 DP_IN and DM_IN Protection
        3. 10.3.11.3 CC IEC and OVP Protection
      12. 10.3.12 Cable Compensation
        1. 10.3.12.1 Cable Compensation Design Example
      13. 10.3.13 USB Port Control
      14. 10.3.14 FAULT Response
      15. 10.3.15 USB Specification Overview
      16. 10.3.16 USB Type-C® Basics
        1. 10.3.16.1 Configuration Channel
        2. 10.3.16.2 Detecting a Connection
        3. 10.3.16.3 Configuration Channel Pins CC1 and CC2
        4. 10.3.16.4 Current Capability Advertisement and VCONN Overload Protection
        5. 10.3.16.5 Plug Polarity Detection
      17. 10.3.17 Device Power Pins (IN, CSN/OUT, and PGND)
      18. 10.3.18 Thermal Shutdown
      19. 10.3.19 Power Wake
    4. 10.4 Device Functional Modes
      1. 10.4.1 Shutdown Mode
      2. 10.4.2 Standby Mode
      3. 10.4.3 Active Mode
      4. 10.4.4 Device Truth Table (TT)
      5. 10.4.5 USB Port Operating Modes
        1. 10.4.5.1 USB Type-C® Mode
        2. 10.4.5.2 Standard Downstream Port (SDP) Mode — USB 2.0, USB 3.0, and USB 3.1
        3. 10.4.5.3 Charging Downstream Port (CDP) Mode
        4. 10.4.5.4 Client Mode
      6. 10.4.6 High-Bandwidth Data-Line Switches
  11. 11Application and Implementation
    1. 11.1 Application Information
    2. 11.2 Typical Application
      1. 11.2.1 Design Requirements
      2. 11.2.2 Detailed Design Procedure
        1. 11.2.2.1  Output Voltage
        2. 11.2.2.2  Switching Frequency
        3. 11.2.2.3  Inductor Selection
        4. 11.2.2.4  Output Capacitor Selection
        5. 11.2.2.5  Input Capacitor Selection
        6. 11.2.2.6  Bootstrap Capacitor Selection
        7. 11.2.2.7  VCC Capacitor Selection
        8. 11.2.2.8  Enable and Undervoltage Lockout Set-Point
        9. 11.2.2.9  Current Limit Set-Point
        10. 11.2.2.10 Cable Compensation Set-Point
        11. 11.2.2.11 LD_DET, POL, and FAULT Resistor Selection
      3. 11.2.3 Application Curves
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Ground Plane and Thermal Considerations
    3. 13.3 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Documentation Support
      1. 14.1.1 Related Documentation
    2. 14.2 Related Links
    3. 14.3 ドキュメントの更新通知を受け取る方法
    4. 14.4 サポート・リソース
    5. 14.5 Trademarks
    6. 14.6 静電気放電に関する注意事項
    7. 14.7 用語集
  15. 15Mechanical, Packaging, and Orderable Information

13.2 Ground Plane and Thermal Considerations

It is recommended to use one of the middle layers as a solid ground plane. Ground plane provides shielding for sensitive circuits and traces. It also provides a quiet reference potential for the control circuitry. The PGND pins should be connected to the ground plane using vias right next to the bypass capacitors. PGND pin is connected to the source of the internal LS switch. The PGND net contains noise at switching frequency and may bounce due to load variations. PGND trace, as well as VIN and SW traces, should be constrained to one side of the ground plane. The other side of the ground plane contains much less noise and should be used for sensitive routes. AGND and PGND should be connected under the QFN package PAD.

It is recommended to provide adequate device heat sinking by utilizing the PAD of the IC as the primary thermal path. Use a minimum 2 row, 2 column "+" array of 12 mil thermal vias to connect the PAD to the system ground plane heat sink. The vias should be evenly distributed under the PAD. Use as much copper as possible, for system ground plane, on the top and bottom layers for the best heat dissipation. Use a four-layer board with the copper thickness for the four layers, starting from the top of, 2 oz / 1 oz / 1 oz / 2 oz. Four layer boards with enough copper thickness provide low current conduction impedance, proper shielding and lower thermal resistance.

The thermal characteristics of the TPS2583x-Q1 are specified using the parameter θJA, which characterize the junction temperature of silicon to the ambient temperature in a specific system. Although the value of θJA is dependent on many variables, it still can be used to approximate the operating junction temperature of the device. To obtain an estimate of the device junction temperature, one may use the following relationship:

Equation 15. TJ = PD × θJA + TA

where

TJ = Junction temperature in °C

PD = VIN × IIN × (1 – Efficiency) – 1.1 × IOUT2 × DCR in Watt

DCR = Inductor DC parasitic resistance in Ω

θJA = Junction to ambient thermal resistance of the device in °C/W

TA = Ambient temperature in °C

θJA is highly related to PCB size and layout, as well as environmental factors such as heat sinking and air flow.