SPRADQ1 February   2025 TMS320F2800133 , TMS320F2800135 , TMS320F2800137 , TMS320F2800155 , TMS320F2800157 , TMS320F280025C , TMS320F280037C-Q1 , TMS320F280039C , TMS320F280039C-Q1 , TMS320F280045 , TMS320F280049 , TMS320F280049C , TMS320F28P559SJ-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Potential Risks with Traditional PWM Configuration
  6. 3PWM Configurations for Robust Control
    1. 3.1 Create Additional Delay for the Sync Event for the PWM Counter
    2. 3.2 Configure a ZCD Signal as a T1 Event
  7. 4How to Capture the Phase Difference and Period of Multiphase Totem Pole PFCs
  8. 5How to Eliminate the External ZCD Circuits with TI GaN
  9. 6Summary
  10. 7References

1 Introduction

Requirements for PFCs have undergone considerable changes over the last few years due to increasing demands for smaller size and higher efficiency. The challenge to meet premium levels of 80 plus standards requires very high efficiency over wide operating input and output ranges. This requirement for high efficiency has generated considerable interest in bridgeless topologies for the PFC stage (including totem pole PFC) that can push efficiency above 99%. Compared with hard switching control, a TCM totem pole PFC is increasingly popular due to the merits of zero-voltage switching (ZVS). With the addition of a gallium nitride (GaN) high electron mobility transistor (HEMT), the switching frequency of the TCM totem pole PFC can be pushed to MHz. To optimize system performance, TI also released intelligent GaN with integrated zero crossing detection (ZCD) functions to help reduce BOM cost and simplify software control.

This paper discusses how to leverage advanced features of the C2000 microcontroller (MCU) and the ZCD features of TI GaN to achieve robust and simple software control and system design, including techniques on how to implement interleaving control.