Hybrid Interleaving Structure With Adaptive PLL Loop For Constant On-Time Switching Converter

A simple interleaving method is propsed to improve transient response and remain pseudo constant frequency for constant on-time controlled multi-phase switching converters. Currently, pulse distribution and PLL methods are used for interleaving. Former is simple, but is noise-sensitive under current ripple cancellation. Besides, the transient response is limited by adding external ramp for noise issue and by inability to synchronize duty cycle. Latter is less noise-sensitive and allows duty cycle overlapping for faster response. However, the PLL loop in each phase is difficult to optimize under wide duty cycle range, and circuit complexity increases for more phases. Therefore, this invention develops a hybrid interleaving technique with comparable transient response as PLL method but much simpler. Also, an adaptive PLL loop is proposed for easier design and regulating constant frequency quickly without interfering constant on control loop.
Patent Information:
For Information, Contact:
Li Chen
Licensing Associate
Virginia Tech Intellectual Properties, Inc.
(540) 443-9217
Pei-Hsin Liu
Fred Lee
Qiang Li