SLVU677A August   2012  – August 2021 TPS54494

 

  1.   Trademarks
  2. 1Introduction
  3. 2Performance Specification Summary
  4. 3Modifications
    1. 3.1 Output Voltage Setpoint
    2. 3.2 Output Filter and Closed-Loop Response
  5. 4Test Setup and Results
    1. 4.1 Input/Output Connections
    2. 4.2 Start-Up Procedure
    3. 4.3 Efficiency
      1. 4.3.1 Efficiency of Converter 1
      2. 4.3.2 Efficiency of Converter 2
    4. 4.4 Load Regulation
      1. 4.4.1 Load Regulation of Converter 1
      2. 4.4.2 Load Regulation of Converter 2
    5. 4.5 Line Regulation
      1. 4.5.1 Line Regulation Converter 1
      2. 4.5.2 Line Regulation Converter 2
    6. 4.6 Load Transient Response
      1. 4.6.1 Load Transient Response Converter 1
      2. 4.6.2 Load Transient Response Converter 2
    7. 4.7 Output Voltage Ripple
      1. 4.7.1 Output Voltage Ripple Converter 1
      2. 4.7.2 Output Voltage Ripple Converter 2
    8. 4.8 Input Voltage Ripple
    9. 4.9 Start-Up
      1. 4.9.1 Converter 1 Start-Up
      2. 4.9.2 Converter 2 Start-Up
  6. 5Board Layout
    1. 5.1 Layout
  7. 6Schematic, Bill of Materials, and Reference
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
    3. 6.3 Reference
  8. 7Revision History

Introduction

The TPS54494 is a dual, adaptive on-time, D-CAP2™-mode, synchronous buck converter requiring a low, external component count. The D-CAP2 control circuit is optimized for low-ESR output capacitors such as POSCAP, SP-CAP, or ceramic types and features fast transient response with no external compensation. The switching frequency is internally set at a nominal of 700 kHz. The high-side and low-side switching MOSFETs are incorporated inside the TPS54494 package along with the gate drive circuitry. The low, drain-to-source on-resistance of the MOSFETs allows the TPS54494 to achieve high efficiencies and helps keep the junction temperature low at high-output currents. The TPS54494 also features auto-skip Eco-mode operation for improved light-load efficiency. The TPS54494 dual DC/DC synchronous converter is designed to provide up to 4 A output on CH1 and 2 A output on CH2 from an input voltage source of 4.5 V to 18 V. The output voltage range is from 0.76 V to 7 V. Rated input voltage and output current range for the evaluation module are given in Table 1-1.

The TPS54494EVM evaluation module is a dual, synchronous buck converter providing 3.3 V at 4 A on CH1 and 1.5 V at 2 A on CH2. This user’s guide describes the TPS54494 EVM performance.

Note:

Throughout the document, x means 1 or 2, for example, VFBx means VFB1 or VFB2.

Table 1-1 Input Voltage, Output Voltage and Output Current Summary
TPS54494EVMInput Voltage RangeOutput VoltageOutput Current Range
CH1VIN1 = 6 V to 18 V3.3 V0 A to 4 A
CH2VIN2 = 5 V to 18 V1.5 V0 A to 2 A