一种绿色模式开关电源控制芯片设计  

A Green Mode Switch Power Control Chip Design

作　　者：李晴平 赵梦恋[1] 

机构地区：[1]浙江大学超大规模集成电路设计研究所,浙江杭州310027

出　　处：《电子技术（上海）》2017年第6期32-36,共5页Electronic Technology

摘　　要：为了提高开关电源全负载下的效率,尤其在轻载或空载下具有与满载相当的效率,本文提出一种绿色模式开关电源的控制芯片设计,使其能根据负载大小调节开关管工作频率:在满载或重载时,系统工作在固定的开关频率,此时采用传统的PWM控制方式;在轻载时,引入绿色模式模块来降低振荡器产生的振荡频率进而降低开关管的开关频率。而开关电源的效率会随着开关电源开关频率的降低而升高,主要是因为开关频率的降低会减少开关管的开关损耗和驱动损耗。在此该绿色模式控制方式基于一反激式峰值电流模式控制的开关电源上得以实现。芯片设计采用CSMC工艺,,仿真结果表明当负载在0A^1A的范围时效率提升最大可达31.9%。To improve the efficiency of switching power supply under the full load, especially light load, this paper presents a green mode control method, which could adjusts the working frequency of the switch transistor according to its load. In full or overloading, the system worked at a fixed switching frequency, and the traditional PWM control mode is adopted; in light load, the oscillation frequency of the oscillator is reduced by the introduction of the green mode module, then the switching frequency of the switch transistor decreased. And the efficiency of switching power supply will be increase with the decrease of the switching frequency, because the decrease of switch frequency would increase the switch losses and the drive losses of the power transistor. The green mode control mode is implemented in a peak current mode flyback convertor. Under the CSMC process, the efficiency of the simulation with load from 1A to 0A is up to 31.9%.

关 键 词：效率 轻载 绿色模式 开关频率 反激式峰值电流模式 

分 类 号：TN86[电子电信—信息与通信工程]