TIDT262 April   2022

 

  1.   Description
  2.   Features
  3.   Applications
  4. 1Test Prerequisites
    1. 1.1 Voltage and Current Requirements
    2. 1.2 Considerations
    3. 1.3 Dimensions
  5. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Load Regulation
    3. 2.3 Line Regulation
    4. 2.4 Thermal Images
      1. 2.4.1 Further Extensive Thermal Measurements
        1. 2.4.1.1 No Forced Cooling
          1. 2.4.1.1.1 Thermal Images 4.5 VIN and 20 AOUT
            1. 2.4.1.1.1.1 After 1 Minute of Operation
            2. 2.4.1.1.1.2 After 2 Minutes of Operation
          2. 2.4.1.1.2 Thermal Image 5.5 VIN and 20 AOUT
          3. 2.4.1.1.3 Thermal Image 7 VIN and 25 AOUT
          4. 2.4.1.1.4 Thermal Image 9 VIN and 30 AOUT
          5. 2.4.1.1.5 Thermal Image 12 VIN and 30 AOUT
          6. 2.4.1.1.6 Thermal Image 15 VIN and 30 AOUT
          7. 2.4.1.1.7 Thermal Image 13.8 VIN and 30 AOUT
        2. 2.4.1.2 Forced Cooling
          1. 2.4.1.2.1 Thermal Image 4.5 VIN and 20 AOUT
          2. 2.4.1.2.2 Thermal Image 5.5 VIN and 20 AOUT
          3. 2.4.1.2.3 Thermal Image 7 VIN and 25 AOUT
          4. 2.4.1.2.4 Thermal Image 9 VIN and 30 AOUT
          5. 2.4.1.2.5 Thermal Image 12 VIN and 30 AOUT
          6. 2.4.1.2.6 Thermal Image 15 VIN and 30 AOUT
    5. 2.5 Bode Plots
  6. 3Waveforms
    1. 3.1 Switching
      1. 3.1.1 9-V Input Voltage (Boost Mode)
        1. 3.1.1.1 Boost High Side FETs (Q5, Q6)
          1. 3.1.1.1.1 Source-Drain (Referenced to VOUT')
          2. 3.1.1.1.2 Gate-Source
        2. 3.1.1.2 Boost Low Side (Q7, Q8)
          1. 3.1.1.2.1 Drain-GND
          2. 3.1.1.2.2 Gate-GND
      2. 3.1.2 12-V Input Voltage, Transition Mode, Both Legs Switching at ½ FSW
        1. 3.1.2.1 Boost High Side FETs (Q5, Q6)
          1. 3.1.2.1.1 Source-Drain (Referenced to VOUT')
          2. 3.1.2.1.2 Gate-Source
        2. 3.1.2.2 Boost Low Side (Q7, Q8)
          1. 3.1.2.2.1 Drain-GND
          2. 3.1.2.2.2 Gate-GND
      3. 3.1.3 16-V Input Voltage, Buck Mode
        1. 3.1.3.1 Buck High Side FETs (Q1, Q2)
          1. 3.1.3.1.1 Source-Drain (Referenced to VIN')
          2. 3.1.3.1.2 Gate-Source
        2. 3.1.3.2 Buck Low Side (Q3, Q4)
          1. 3.1.3.2.1 Drain-GND
          2. 3.1.3.2.2 Gate-GND
    2. 3.2 Output Voltage Ripple
    3. 3.3 Input Voltage Ripple
      1. 3.3.1 Power Stage
      2. 3.3.2 Input Terminal, Differential Input Filter Acting
    4. 3.4 Load Transients
      1. 3.4.1 9-V Input Voltage
      2. 3.4.2 12-V Input Voltage
      3. 3.4.3 16-V Input Voltage
    5. 3.5 Start-Up Sequence
      1. 3.5.1 9-V Input Voltage
      2. 3.5.2 12-V Input Voltage
      3. 3.5.3 16-V Input Voltage
    6. 3.6 Shutdown Sequence
      1. 3.6.1 9-V Input Voltage
      2. 3.6.2 12-V Input Voltage
      3. 3.6.3 16-V Input Voltage

Description

The circuit is an automotive four-switch buck-boost converter circuit using the LM5176-Q1 controller IC, so the power supply is able to step up and step down the input voltage.

The circuit accepts an input voltage of 4.5 V to 27 V and provides a regulated output of 12 V that can deliver up to 30 A, depending on cranking level, cranking time, thermal interface, and maximum ambient temperature.

The purpose of this is design is to squeeze a single power stage to maximum output current.