SDAA026 June   2025 TPSI3052

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Using a Solid-State Relay as an Isolated 15V Supply
  6. 3Topology of Totem Pole PFC for Applying Turn On Switch
  7. 4Original Implementation for Driving PFC Slow Switch at High-side and Low-side
  8. 5Achieving Performance for Driving PFC Slow Switch at High-side and Low-side
  9. 6Test Results Comparing Before and After for High-side Implementation
  10. 7Summary
  11. 8References

6 Test Results Comparing Before and After for High-side Implementation

Figure 6-1 is the waveform before the change that caused the issue. As a result of adding and operating the improved circuit, the high-side FET (Q1) operates normally as shown in Figure 6-2. The entire system operates normally, and the temperature and efficiency are improved.

Waveform of Original Circuit for Operating PFC Slow Switch at High-Side (Q1)
A. CH1 (Yellow): VCC_P, CH2 (Red): VB Pin, CH4 (Green): PFC low side Vgs
Figure 6-1 Waveform of Original Circuit for Operating PFC Slow Switch at High-Side (Q1)
Waveform of Applying Circuit for operating PFC Slow Switch at High-Side (Q1)
A. CH1 (Yellow): 3.3V Input, CH2 (Red): Vdrv Pin, CH4 (Green): PFC low-side Vgs
Figure 6-2 Waveform of Applying Circuit for operating PFC Slow Switch at High-Side (Q1)