SLUSDN6A September   2019  – December 2020 TPSM82810 , TPSM82813

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and 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 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Schematic
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Precise Enable (EN)
      2. 9.3.2 Output Discharge
      3. 9.3.3 COMP/FSET
      4. 9.3.4 MODE/SYNC
      5. 9.3.5 Spread Spectrum Clocking (SSC) - TPSM8281xS
      6. 9.3.6 Undervoltage Lockout (UVLO)
      7. 9.3.7 Power-Good Output (PG)
      8. 9.3.8 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Pulse Width Modulation (PWM) Operation
      2. 9.4.2 Power Save Mode Operation (PFM/PWM)
      3. 9.4.3 100% Duty-Cycle Operation
      4. 9.4.4 Current Limit and Short Circuit Protection
      5. 9.4.5 Soft Start / Tracking (SS/TR)
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Programming the Output Voltage
        2. 10.2.2.2 Feedforward capacitor
        3. 10.2.2.3 Input Capacitor
        4. 10.2.2.4 Output Capacitor
        5. 10.2.2.5 Application Curves
    3. 10.3 System Examples
      1. 10.3.1 Voltage Tracking
      2. 10.3.2 Synchronizing to an External Clock
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
      1. 12.2.1 Thermal Consideration
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

12.1 Layout Guidelines

A proper layout is critical for the operation of any switched mode power supply, especially at high switching frequencies. Therefore, the PCB layout of the TPSM8281x demands careful attention to ensure best performance. A poor layout can lead to issues like bad line and load regulation, instability, increased EMI radiation, and noise sensitivity. Refer to the Five Steps to a Great PCB Layout for a Step-Down Converter Technical Brief for a detailed discussion of general best practices. Specific recommendations for the device are listed below.

  • The input capacitor should be placed as close as possible to the VIN and GND pins of the device. This is the most critical component placement. Route the input capacitor directly to the VIN and GND pins avoiding vias.
  • Place the output capacitor ground close to the VOUT and GND pins and route it directly avoiding vias.
  • Place the FB resistors, R1 and R2, and the feedforward capacitor CFF close to the FB pin and place CSS close to the SS/TR pin to minimize noise pickup.
  • Place the RCF resistor close to the COMP/FSET pin to minimize the parasitic capacitance.
  • The recommended layout is implemented on the EVM and shown in its TPSM82810EVM-089 Evaluation Module User's Guide and in Section 12.2.
  • The recommended land pattern for the TPSM8281x is shown at the end of this data sheet. For best manufacturing results, it is important to create the pads as solder mask defined (SMD), when some pins (such as VIN, VOUT, and GND) are connected to large copper planes. Using SMD pads keeps each pad the same size and avoids solder pulling the device during reflow.