SLUSDN6B September   2019  – July 2024 TPSM82810 , TPSM82813

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Schematic
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Precise Enable (EN)
      2. 8.3.2 Output Discharge
      3. 8.3.3 COMP/FSET
      4. 8.3.4 MODE/SYNC
      5. 8.3.5 Spread Spectrum Clocking (SSC) - TPSM8281xS
      6. 8.3.6 Undervoltage Lockout (UVLO)
      7. 8.3.7 Power-Good Output (PG)
      8. 8.3.8 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 (PFM/PWM)
      3. 8.4.3 100% Duty-Cycle Operation
      4. 8.4.4 Current Limit and Short Circuit Protection
      5. 8.4.5 Soft Start / Tracking (SS/TR)
  10. 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 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Programming the Output Voltage
        3. 9.2.2.3 Feedforward capacitor
        4. 9.2.2.4 Input Capacitor
        5. 9.2.2.5 Output Capacitor
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 Voltage Tracking
      2. 9.3.2 Synchronizing to an External Clock
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
        1. 9.5.2.1 Thermal Consideration
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
      2. 10.1.2 Custom Design With WEBENCH® Tools
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9.5.1 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 analog design journal for a detailed discussion of general best practices. Specific recommendations for the device are listed below.

  • The input capacitor must 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 the 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.