TIDT391 April   2024

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5. 1Test Prerequisites
    1. 1.1 Voltage and Current Requirements
    2. 1.2 Required Equipment
    3. 1.3 Dimensions
    4. 1.4 Test Setup
  6. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Efficiency Data
    3. 2.3 Thermal Images
  7. 3Waveforms
    1. 3.1 Start-Up Sequence
    2. 3.2 Switching
    3. 3.3 Short-Circuit Protection

3.2 Switching

Figure 3-20 through Figure 3-10 show the power stage waveform at different working modes in BQ25756E among buck mode, buck-boost mode, and boost mode with seamless transition. The switching frequency is set to 300kHz.

GUID-20240407-SS0I-PPPT-XXJQ-HXHPHBKZGNC5-low.pngFigure 3-5 Boost Mode Switching Node Waveform VIN = 5V, Battery Voltage = 30V
GUID-20240407-SS0I-VD5P-K0GJ-GLZWXPHFBX4Z-low.pngFigure 3-7 Boost Mode Switching Node Waveform VIN = 15V, Battery Voltage = 30V
GUID-20240407-SS0I-GGBV-XKH7-JCJ3RDV1GPDF-low.pngFigure 3-9 Buck Mode Switching Node Waveform VIN = 20V, Battery Voltage = 16V
GUID-20240407-SS0I-9SF1-NGGZ-ZPFSCVZB5K8G-low.pngFigure 3-6 Boost Mode Switching Node Waveform VIN = 9V, Battery Voltage = 30V
GUID-20240407-SS0I-WVCX-TBMT-RBD5JSB5QG3D-low.pngFigure 3-8 Boost Mode Switching Node Waveform VIN = 20V, Battery Voltage = 30V
GUID-20240407-SS0I-SPMW-JHD0-FMCVQTJS3VDW-low.pngFigure 3-10 Buck-Boost Mode Switching Node Waveform VIN = 20V, Battery Voltage = 20V