Soft start of a Synchronous Rectifier Buck Converter with Pre-biased Output
Date Issued
2005
Date
2005
Author(s)
Chen, Pei-Yuan
DOI
zh-TW
Abstract
Abstract
A synchronous Buck dc/dc converter with current sourcing and sinking capabilities is required in low-voltage Double Data Rate Memory (DDR) applications. In many Buck converter applications, soft start of the main MOSFET switch with pre-biased output voltage condition is often necessary to avoid undesirable effects such as in-rush start current, possible inductor saturation, and output voltage overshoot. However, in a synchronous Buck converter configuration, such starting condition would lead to output voltage temporary dipping, which is disallowed in many applications.
In this thesis, a control scheme to avoid such a problem is proposed and circuit-level SPICE simulations were conducted to verify the concept. And the proposed circuit concept was experimentally verified by using discrete components at the breadboard level. Although the implementation was done with discrete components, however, the scheme was conceived with the final intention of integrated circuit fabrication.
Subjects
同步整流降壓型轉換器
緩啟動
預偏電壓
電壓突降
湧入電流
Synchronous rectifier Buck converter
Soft-start
Pre-bias voltage
voltage dipping
Inrush current
Type
thesis