JAJSBM1E November   2011  – October 2021 TPS62150 , TPS62150A , TPS62151 , TPS62152 , TPS62153

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 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings (1)
    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. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Enable / Shutdown (EN)
      2. 8.3.2 Soft Start or Tracking (SS/TR)
      3. 8.3.3 Power Good (PG)
      4. 8.3.4 Pin-Selectable Output Voltage (DEF)
      5. 8.3.5 Frequency Selection (FSW)
      6. 8.3.6 Undervoltage Lockout (UVLO)
      7. 8.3.7 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Pulse-Width Modulation (PWM) Operation
      2. 8.4.2 Power-Save Mode Operation
      3. 8.4.3 100% Duty-Cycle Operation
      4. 8.4.4 Current-Limit and Short-Circuit Protection
  9. 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 Programming the Output Voltage
        2. 9.2.2.2 External Component Selection
          1. 9.2.2.2.1 Inductor Selection
          2. 9.2.2.2.2 Capacitor Selection
            1. 9.2.2.2.2.1 Output Capacitor
            2. 9.2.2.2.2.2 Input Capacitor
            3. 9.2.2.2.2.3 Soft-Start Capacitor
        3. 9.2.2.3 Tracking Function
        4. 9.2.2.4 Output Filter and Loop Stability
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 LED Power Supply
      2. 9.3.2 Active Output Discharge
      3. 9.3.3 Inverting Power Supply
      4. 9.3.4 Various Output Voltages
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
      1. 11.2.1 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 サポート・リソース
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

11.1 Layout Guidelines

Proper layout is critical for the operation of a switched-mode power supply, even more at high switching frequencies. Therefore, the PCB layout of the TPS6215x device demands careful attention to ensure operation and to get the performance specified. A poor layout can lead to issues like poor regulation (both line and load), stability and accuracy weaknesses, increased EMI radiation, and noise sensitivity.

See Figure 11-1 for the recommended layout of the TPS6215x device, which is designed for common external ground connections. Both AGND (pin 6) and PGND (pins 15 and 16) are directly connected to the exposed thermal pad. On the PCB, the direct common-ground connection of AGND and PGND to the exposed thermal pad and the system ground (ground plane) is mandatory. Also, connect VOS (pin 14) in the shortest way to VOUT at the output capacitor. To avoid noise coupling into the VOS line, this connection should be separated from the VOUT power line and plane as shown in Section 11.2.

Provide low-inductance and -resistance paths for loops with high di/dt. Paths conducting the switched load current should be as short and wide as possible. Provide low-capacitance paths (with respect to all other nodes) for wires with high dv/dt. The input and output capacitance should be placed as close as possible to the IC pins, and parallel wiring over long distances as well as narrow traces should be avoided. Loops which conduct an alternating current should outline an area as small as possible, as this area is proportional to the energy radiated.

Sensitive nodes like FB (pin 5) and VOS (pin 14) must be connected with short wires and not near high dv/dt signals [for example, SW (pins 1, 2, and 3)]. As FB and VOS pins carry information about the output voltage, they should be connected as closely as possible to the actual output voltage (at the output capacitor). The capacitor on SS/TR (pin 9) and on AVIN (pin 19), as well as the FB resistors, R1 and R2, should be kept close to the IC and connect directly to those pins and the system ground plane.

The exposed thermal pad must be soldered to the circuit board for mechanical reliability and to achieve adequate power dissipation.

The recommended layout is implemented on the EVM and shown in its Users Guide, SLVU437. Additionally, the EVM Gerber data are available for download here, SLVC394.