SLVU504A September   2011  – August 2021 TPS54623

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Background
    2. 1.2 Performance Specification Summary
    3. 1.3 Modifications
      1. 1.3.1 Output Voltage Set Point
      2. 1.3.2 Slow-Start Time
      3. 1.3.3 Track In
      4. 1.3.4 Adjustable UVLO
      5. 1.3.5 Input Voltage Rails
  3. 2Test Setup and Results
    1. 2.1  Input/Output Connections
    2. 2.2  Efficiency
    3. 2.3  Output Voltage Load Regulation
    4. 2.4  Output Voltage Line Regulation
    5. 2.5  Load Transients
    6. 2.6  Loop Characteristics
    7. 2.7  Output Voltage Ripple
    8. 2.8  Input Voltage Ripple
    9. 2.9  Powering Up
    10. 2.10 Prebias Start-Up
    11. 2.11 Hiccup Mode Current Limit
  4. 3Board Layout
    1. 3.1 Layout
  5. 4Schematic and Bill of Materials
    1. 4.1 Schematic
    2. 4.2 Bill of Materials
  6. 5Revision History

Layout

The board layout for the TPS54623EVM-012 is shown in Figure 3-1 through Figure 3-5. The top-side layer of the EVM is laid out in a manner typical of a user application. The top, bottom, and internal layers are 2-oz. copper.

The top layer contains the main power traces for PVIN, VIN, VOUT, and VPHASE. Also on the top layer are connections for the remaining pins of the TPS54623 and a large area filled with ground. The bottom and internal ground layers contain ground planes only. The top-side ground traces are connected to the bottom and internal ground planes with multiple vias placed around the board including two vias directly under the TPS54623 device to provide a thermal path from the top-side ground plane to the bottom-side ground plane.

The input decoupling capacitors (C1 and C2) and bootstrap capacitor (C3) are all located as close to the IC as possible. Additionally, the voltage set-point resistor divider components are kept close to the IC. The voltage divider network ties to the output voltage at the point of regulation, the copper VOUT trace at the J2 output connector. For the TPS54623, an additional input bulk capacitor may be required, depending on the EVM connection to the input supply. Critical analog circuits such as the voltage setpoint divider, frequency set resistor, slow-start capacitor, and compensation components are terminated to ground using a wide ground trace separate from the power ground pour.

GUID-8ADD1AFC-8130-4D03-86E2-264082FF8F30-low.gifFigure 3-1 TPS54623EVM-012 Top-Side Layout
GUID-531AEC37-3F4B-46B2-90AD-1CD392908BAA-low.gifFigure 3-3 TPS54623EVM-012 Layout 3
GUID-00D1F217-9BFA-46CF-8589-A196F402B1F6-low.gifFigure 3-5 TPS54623EVM-012 Top-Side Assembly
GUID-CDF5E7CE-9926-4314-9E12-C3B71255E38A-low.gifFigure 3-2 TPS54623EVM-012 Layout 2
GUID-BAF062A2-D4C1-440E-A9CF-8A4CB4FCE726-low.gifFigure 3-4 TPS54623EVM-012 Bottom-Side Layout