TIDT322 august   2023

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5. 1Test Prerequisites
    1. 1.1 Design Requirements
    2. 1.2 Required Equipment
    3. 1.3 Considerations
    4. 1.4 Dimensions
  6. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Efficiency Data
    3. 2.3 Thermal Images
    4. 2.4 Bode Plots
    5. 2.5 EMI
  7. 3Waveforms
    1. 3.1 Switching
    2. 3.2 Output Voltage Ripple
    3. 3.3 Short-Circuit Protection
    4. 3.4 Load Transients
    5. 3.5 Start-Up Sequence

Description

This 4-phase reference design provides 3.3-V out at 24 A from a 3.8-V to 16-V automotive power source. The circuit uses two LMQ644A2-Q1 dual-channel synchronous buck regulators operating at a nominal switching frequency of 500 kHz. Forced Pulse Width Modulation (FPWM) or Pulse Frequency Modulation (PFM) for light load operation is jumper selectable. Test points are provided for frequency synchronization, power good, and frequency response injection.