摘要
采用折返式电路,设计了一种适用于USB电源管理芯片的双门限限流保护电路。通过改变参考电流,进而改变比较器参考电压的方式,使系统在发生过流时输出恒定电流,发生短路时实现门限降低,以达到更低的恒定输出电流。采用UMC 0.5μm CMOS工艺,运用Cadence和Hspice进行仿真验证,温度在-40℃~120℃变化时,过流门限和短路门限仅变化2.1%和1.5%。不同工艺角下,均满足系统要求。
A double threshold current limiting protection circuit with foldback circuit for USB power management chip was designed. The reference voltage of comparator was changed by adjusting the reference current. When an over current occurred, the circuit＇s output kept constant current, and when a short circuit occurred, the threshold was reduced to maintain a lower constant output current. The circuit was simulated with Cadence and Hspice software based on the UMC 0.5 μm CMOS technology library. Simulation results showed that over-current threshold and short-circuit threshold varied only 2.1% and 1.5 % respectively when the temperature was changing from -40 ℃ to 120 ℃. The circuit met the system＇s requirement at different corners.
出处
《微电子学》
CAS
CSCD
北大核心
2015年第4期429-432,共4页
Microelectronics
基金
国家自然科学基金资助项目(61271090)
四川省科技支撑计划项目(2015GZ0103)
关键词
限流电路
电源管理芯片
双门限
恒流输出
Current limiting circuit
Power management chip
Double threshold
Constant current output
