SNVU872A September   2023  – March 2024 LM70880-Q1

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  7. 2Hardware
    1. 2.1 Test Setup and Procedure
      1. 2.1.1 EVM Connections
      2. 2.1.2 Test Equipment
      3. 2.1.3 Recommended Test Setup
        1. 2.1.3.1 Input Connections
        2. 2.1.3.2 Output Connections
      4. 2.1.4 Test Procedure
        1. 2.1.4.1 Line and Load Regulation, Efficiency
  8. 3Implementation Results
    1. 3.1 Performance Data and Results
      1. 3.1.1 EVM Characteristics
      2. 3.1.2 Conversion Efficiency
      3. 3.1.3 Operating Waveforms
        1. 3.1.3.1 Switching
        2. 3.1.3.2 Load Transient Response
        3. 3.1.3.3 Line Transient Response
        4. 3.1.3.4 Start-Up and Shutdown With EN
        5. 3.1.3.5 Start-Up with VIN
      4. 3.1.4 Bode Plot
      5. 3.1.5 CISPR 25 EMI Performance
      6. 3.1.6 Thermal Performance
  9. 4Hardware Design Files
    1. 4.1 Schematic
    2. 4.2 PCB Layout
      1. 4.2.1 Component Drawings
      2. 4.2.2 Multi-Layer Stackup
    3. 4.3 Bill of Materials
  10. 5Compliance Information
    1. 5.1 Compliance and Certifications
  11. 6Related Documentation
    1. 6.1 Supplemental Content
      1. 6.1.1 Development Support
      2. 6.1.2 PCB Layout Resources
      3. 6.1.3 Thermal Design Resources
  12. 7Additional Information
    1. 7.1 Trademarks
  13. 8Revision History

2.1.2 Test Equipment

Voltage Source: Use an input voltage source capable of supplying 0V to 80V and 12A.

Multimeters:

  • Voltmeter 1: Input voltage at VIN+ to VIN–. Set the voltmeter to an input impedance of 100MΩ.
  • Voltmeter 2: Output voltage at VOUT to GND. Set the voltmeter to an input impedance of 100MΩ.
  • Ammeter 1: Input current. Set the ammeter to 1-second aperture time.
  • Ammeter 2: Output current. Set the ammeter to 1-second aperture time.

Electronic Load: The load must be an electronic constant-resistance (CR) or constant-current (CC) mode load capable of 0ADC to 10ADC at 5V. For a no-load input current measurement, disconnect the electronic load as the load can draw a small residual current.

Oscilloscope: With the scope set to 20MHz bandwidth and AC coupling, measure the output voltage ripple directly across an output capacitor with a short ground lead normally provided with the scope probe. Place the oscilloscope probe tip on the positive terminal of the output capacitor, holding the ground barrel of the probe through the ground lead to the negative terminal of the capacitor. TI does not recommend using a long-leaded ground connection because this can induce additional noise given a large ground loop. To measure other waveforms, adjust the oscilloscope as needed.

Safety: Always use caution when touching any circuits that can be live or energized.