TIDT256A March   2022  – March 2022

 

  1.   Description
  2.   Features
  3.   Applications
  4. 1Test Prerequisites
    1. 1.1 LM5156-Q1
      1. 1.1.1 Loading LM5156-Q1
      2. 1.1.2 LM5156-Q1 SEPIC Bode Loop Testing
    2. 1.2 Loading UCC14240-Q1
    3. 1.3 UCC5870-Q1 and UCC5870-Q1 EVM GUI
    4. 1.4 Voltage and Current Requirements
    5. 1.5 Required Equipment
    6. 1.6 Considerations
    7. 1.7 Dimensions
  5. 2Testing and Results
    1. 2.1 SEPIC Efficiency Graphs
    2. 2.2 SEPIC Efficiency Data
    3. 2.3 SEPIC Bode Plots
    4. 2.4 Thermal Images
  6. 3Waveforms
    1. 3.1 SEPIC Switching
    2. 3.2 SEPIC Output Voltage Ripple
    3. 3.3 SEPIC Load Transients
    4. 3.4 SEPIC Start-Up Sequence
    5. 3.5 Isolated Bias Supply Start Up and Shutdown
    6. 3.6 Isolated Gate Drive

3.6 Isolated Gate Drive

Isolated gate drive waveforms are shown in this section.

GUID-20220322-SS0I-K7MW-GVDJ-XKFPKGLRTRTF-low.jpg
+15 V, –5 V to isolated driver, model t16 used
Scope at full 500-MHz bandwidth
Scope channel two red showing gate voltage versus isolated side ground
Rising (10% to 90%) in 12 ns
Figure 3-17 Rising Waveform - No Load
GUID-20220322-SS0I-VJBL-LBLF-PJWXDHQDPKKV-low.jpg
+15 V, –5 V to isolated driver, model t11 used
Scope at 200-MHz bandwidth
Scope channel two red showing gate voltage versus isolated side ground
Rising (10% to 90%) in 333 ns and falling (90% to 10%) in 326 ns
Figure 3-19 Gate Loaded With 100 nF, 2-μC Charge: One 6-μs Pulse
GUID-20220322-SS0I-DWDG-7GJK-DMK2V550RGPS-low.jpg
+15 V, –5 V to isolated driver, model t16 used
Scope at full 500-MHz bandwidth
Scope channel two red showing gate voltage versus isolated side ground
Falling (90% to 10%) in 14 ns
Figure 3-18 Falling Waveform - No Load
GUID-20220322-SS0I-1GWB-RJ4C-8XLFF3ZB61SK-low.jpg
+15 V, –5 V to isolated driver, model t11 used
Scope at 200-MHz bandwidth
Scope channel two red showing gate voltage versus isolated side ground
Figure 3-20 Gate Loaded With 100 nF, 2-μC Charge: 40 kHz, 50% Duty, 4 Cycles