TIDT349A January   2024  – December 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 Considerations
    4. 1.4 Dimensions
    5. 1.5 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 Charge Mode Start-Up Waveform
    2. 3.2 OTG Mode Start-Up Waveform
    3. 3.3 Voltage Transition at OTG Mode
    4. 3.4 Ripple and Noise at OTG Mode
    5. 3.5 Load Transients at OTG Mode
    6. 3.6 Switching Waveform
    7. 3.7 Overcurrent Protection at OTG Mode
    8. 3.8 Short-Circuit Protection at OTG Mode
    9. 3.9 Short-Circuit Protection at Charge Mode
  8. 4Trademarks

3.6 Switching Waveform

The following images show the power stage waveform at different working modes in BQ25756 among buck mode, buck-boost mode, and boost mode with seamless transition. The switching frequency is set to 300kHz.

PMP41062 Buck Mode
Blue: buck leg switching point, Purple: boost leg switching point
Figure 3-21 Buck Mode
PMP41062 Boost Mode
Blue: buck leg switching point, Purple: boost leg switching point
Figure 3-23 Boost Mode
PMP41062 Buck-Boost Mode
Blue: buck leg switching point, Purple: boost leg switching point
Figure 3-22 Buck-Boost Mode
PMP41062 Switching Leg Waveform at Vsys = 20V, Vbat = 40V Full-Load Charging Mode,fSW = 300kHzFigure 3-24 Switching Leg Waveform at Vsys = 20V, Vbat = 40V Full-Load Charging Mode,
fSW = 300kHz