SLUAAN2 april   2023 TPS543620 , TPS54620 , TPS54J060 , TPS54J061 , TPS566231 , TPS566235 , TPS566238 , TPS566242 , TPS566247

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Features Description
    1. 2.1 Light Load Operation
    2. 2.2 Large Duty Operation
    3. 2.3 BST Cap Integrated
    4. 2.4 Voltage Identification Control
    5. 2.5 Output-voltage Tracking
  5. 3Control Modes Description
    1. 3.1 PCM/ACM
    2. 3.2 D-CAP2™/D-CAP3™
    3. 3.3 Control Modes Comparison
  6. 4Specifications Comparison
  7. 5References

2.2 Large Duty Operation

In the applications where Vout is close to Vin, large duty is needed to support normal regulation. Due to minimum off-time limit, if switching frequency does not change, the maximum duty-cycle is fixed. Large Duty Operation extends the high-side FET on-time, thus decreasing switching frequency and allowing large duty cycles to be maintained. The Large Duty Cycle Operation With the TPS568230 application note describes the details.

Some parts support 100% duty-cycle mode, high-side FET is continuously switched on as long as the BOOT capacitor voltage is higher than preset UVLO threshold.