SNVA790A October   2020  – July 2022 LMR36520

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2 Fly-Buck Converter Device Operation
    1. 2.1 Output Current Equations and Considerations
  5. 3LMR36520 Fly-Buck Converter Design
    1. 3.1 Coupled Inductor
    2. 3.2 Primary Output Capacitor
    3. 3.3 Rectifying Diode
    4. 3.4 Secondary Output Capacitor
    5. 3.5 Preload Resistor
    6. 3.6 Zener Diode
    7. 3.7 Snubber Circuit
  6. 4Experimental Results
    1. 4.1 Steady State
    2. 4.2 Secondary Output Voltage
    3. 4.3 Load Transient
    4. 4.4 Start-up
    5. 4.5 Output Current
  7. 5Conclusion
  8. 6References
  9. 7Revision History

4.5 Output Current

The following output current measurements are shown in more detail to compare with the calculated output capacitor rms currents.

The ACVrms measurement in Figure 4-12 represents the small signal AC component of the primary or secondary winding current waveforms shown. This small signal component is the current that will flow through the output capacitor bank.

GUID-20201218-CA0I-ZDFB-5JW1-MRFQXC8M5D3M-low.gif Figure 4-9 Primary winding Current Measurement at 10 VIN
GUID-20201218-CA0I-FGSJ-KT5G-43PHP0PV6G9J-low.gif Figure 4-10 Primary winding Current Measurement at 36 VIN
GUID-20201218-CA0I-PKPV-KFPX-TMWDX0F0HRDS-low.png Figure 4-11 Secondary Winding Current Measurement at 10 VIN
GUID-20201218-CA0I-TQXN-CC7X-Z006T847FLRF-low.png Figure 4-12 Secondary Winding Current Measurement at 36 VIN