具有预偏置电压保护的软启动电路设计  

Design of Soft-start Circuit with Pre-biased Voltage Protection

作　　者：高家豪 夏晓娟 GAO Jiahao;XIA Xiaojuan(College of Electronics and Optical Engineering&College of Microelectronics,Nanjing University of Posts and Telecommunications,Nanjing,210023,CHN;National and Local Joint Engineering Laboratory for RF Integration and Micro-Assembly Technology,Nanjing University of Posts and Telecommunications,Nanjing,210023,CHN)

机构地区：[1]南京邮电大学电子与光学工程学院、微电子学院,南京210023 [2]南京邮电大学射频集成与微组装技术国家地方联合工程实验室,南京210023

出　　处：《固体电子学研究与进展》2020年第3期211-218,共8页Research & Progress of SSE

基　　金：国家自然科学基金青年基金资助项目(61704088);南京邮电大学教学改革项目(JG03318JX78)。

摘　　要：针对DC/DC转换器上电时存在电压过冲及电流倒灌现象,设计了一种具有预偏置电压保护的软启动电路。其核心在于通过对偏置电流的镜像及分流作用得到微小的电流,以及对复合电容的间歇性充电得到足够的启动时间。同时设计预偏置电压保护逻辑电路,针对不同情况下的启动,有效地控制功率管,使芯片上电时无论输出电压是否为零,输出电压都能够平缓且单调上升,并在软启动完成后关闭模块,减少功耗。基于0.5μm CMOS工艺对电路进行设计与仿真,软启动时间约为1 ms,将其应用于Buck型DC/DC转换器电路中,在电源重新上电,保护模块完成保护后均能够实现软启功能,电路模块面积为0.13 mm×0.09 mm,功耗为0.05 mW。A soft-start circuit with pre-biased voltage protection was designed for the phenomenon of voltage overshoot and current back flow when the DC/DC converter was powered on.The core was to obtain a small current through the mirroring and shunting of the bias current,and to get enough start time by intermittently charging the composite capacitor.At the same time,the pre-biased voltage protection logic circuit was designed to effectively control the power tube for start-up under different circumstances,so that the output voltage could rise gently and monotonically when the chip was powered on,no matter whether the output voltage was zero or not.After the soft-start was completed,the module was turned off to reduce power consumption.The circuit is designed and simulated based on the 0.5μm CMOS process,the time of soft-start is about 1 ms.It is applied to the Buck type DC/DC converter design,and the soft-start function can be realized when the system is powered on again and after the protection module protection is completed.The area of circuit module is only 0.13 mm×0.09 mm,and the power consumption is 0.05 mW.

关 键 词：预偏置电压保护 软启动电路 DC/DC转换器 低功耗 

分 类 号：TN432[电子电信—微电子学与固体电子学]