同步整流降压型DC-DC过零检测电路的设计  

A Design for Zero-detect Circuit of Synchronous Rectification Buck DC-DC Converter

作　　者：王辉[1] 王松林[1] 来新泉[2] 郭宝龙[1] 牟在鑫[1] 

机构地区：[1]西安电子科技大学机电工程学院,西安710071 [2]西安电子科技大学CAD所,西安710071

出　　处：《固体电子学研究与进展》2010年第2期276-280,共5页Research & Progress of SSE

基　　金：国家自然科学基金资助项目(60876023)

摘　　要：同步整流降压型DC-DC工作在不连续电感电流模式(DCM)下会出现的电感电流倒灌现象,这种情况会使得整个系统处于一种超过放状态,从而使系统的效率大幅度地下降。针对这一问题,设计实现了一款电感电流过零检测电路。该电路利用失调电阻抵消同步管关断延迟,达到了快速关断同步管的目的,有效地降低了电流倒灌。且该电路正常工作时的静态电流为5μA,其面积仅有0.005 mm2。采用此电路的一款同步BUCK型DC-DC已在韩国Hynix公司的0.5μm CMOS工艺线投片,测试结果证明过零检测电路效果良好。The phenomenon that inductor current flows backward appears when synchronous rectification buck DC-DC works in DCM（discontinuous conduction mode）.And this will make the whole system working in over-amplified status,thus reducing the efficiency of the whole system greatly.According to this problem a novel zero-detect circuit is designed.By using imbalance resistance to offset the synchronization transistors turning off delay the circuit can realize fast turn-off function and avoid the happening of current backward flowing.The current consumption of this circuit for normal working is only 5 μA and the area is only 0.005 mm2.A DC-DC converter with this anti-ringing circuit is implemented in Hynix 0.5 μm CMOS process,and the testing result proves that the zero-detect circuit works well and effectively.

关 键 词：同步 直流-直流转换器 降压型 过零检测 

分 类 号：TN433[电子电信—微电子学与固体电子学]