SLOA198A September   2014  – December 2021 DRV2665 , DRV2667 , DRV2700 , DRV8662

 

  1.   Trademarks
  2. 1 Boost Converter Basics
  3. 2 DRV8662, DRV2700, DRV2665, and DRV2667 Boost Converter
    1. 2.1 DRV8662, DRV2700, DRV2665, and DRV2667 Boost Converter Efficiency
      1. 2.1.1 Boost Efficiency vs Boost Current
    2. 2.2 DRV8662, DRV2700, DRV2665, and DRV2667 Boost Converter Load Regulation
      1. 2.2.1 Boost Regulation vs Current
  4. 3 Configuring the Boost Converter
  5. 4 Boost Converter Output Voltage
  6. 5 Calculating the Load Current
  7. 6 Selecting an Inductor
    1. 6.1 Inductance Rating
    2. 6.2 Saturation Current Rating
    3. 6.3 Thermal Current Rating
    4. 6.4 Choosing REXT
    5. 6.5 What to Avoid: Using Incorrect Inductor Current Ratings
  8. 7 Calculate the Maximum Boost Current
  9. 8 Output Capacitor Selection
  10. 9 Input Capacitor Selection
  11. 10PCB Layout
    1. 10.1 What to Avoid: Incorrect Inductor Placement
  12. 11Examples
    1. 11.1 Example: Based on the DRV8662EVM
      1. 11.1.1 Configure the Boost Voltage
      2. 11.1.2 Configure the Inductor Current
      3. 11.1.3 Boost Performance Results
    2. 11.2 Example: Based on the DRV2667EVM-CT with 25-nF Piezo Module
      1. 11.2.1 Configure the Boost Voltage
      2. 11.2.2 Configure the Inductor Current
      3. 11.2.3 Boost Performance Results
  13. 12Revision History

11.2.3 Boost Performance Results


The actual load regulation and boost efficiency for the DRV2667EVM-CT are shown in Figure 11-5. The load regulation is a measure of the boost voltage versus the boost output current. In Figure 11-5, the voltage regulation begins to drop above approximately 10 mA of boost output current. Comparing the voltage regulation of the DRV2667EVM-CT to the DRV8662EVM, the DRV2667EVM-CT boost has much less current capacity because of the smaller inductor and current limit resistor settings.

GUID-1588DD37-D057-45DF-8CAC-42B467BEA23B-low.gifFigure 11-5 Boost Voltage vs Boost Current - DRV2667EVM-CT-80 V

The boost efficiency is shown in Figure 11-6. The efficiency data was removed after the boost voltage decreased by more than 5 V.

GUID-6FD05702-2BD5-4FD1-AB90-2F00C25713E1-low.gifFigure 11-6 Efficiency vs Boost Current - VBST = 80 V