一种基于ACOT的Buck型开关电源设计  

Design of Buck Switching Power Supply Based on ACOT

作　　者：谢凌寒 孙祎轩 周颖 荣悦 XIE Linghan;SUN Yixuan;ZHOU Ying;RONG Yue(Wuxi Etek Micro-Electronic Co.,Ltd.,Wuxi 214028,China;School of Integrated Circuits,Southeast University,Nanjing 210096,China)

机构地区：[1]无锡力芯微电子股份有限公司,江苏无锡214028 [2]东南大学集成电路学院,南京210096

出　　处：《电子与封装》2023年第11期80-86,共7页Electronics & Packaging

摘　　要：基于自适应恒定导通时间(ACOT)控制方式,设计了一种恒频效果良好的降压型DC-DC转换器。该转换器采用V2COT架构,兼具输出精度高和瞬态响应速度快的特点。采用一种改进的自适应导通时间控制方式,降低了负载电流对开关频率的影响,使转换器在连续导通模式(CCM)下具有良好的开关频率稳定性。基于东部高科0.15μm BCD工艺完成流片,芯片输入电压为4.5~17 V,输出电压为0.76~7 V,最大负载电流为3 A,开关频率为1 MHz。测试结果表明,在CCM下,开关频率随输入电压变化率为2.67 kHz/V,随负载电流变化率为2.95 kHz/A,峰值效率达96.43%,输出电压纹波为8.2 mV,负载调整率为0.93%,负载瞬态响应时间小于20μs。Based on adaptive constant on time(ACOT)control mode,a step-down DC-DC converter with good constant-frequency effect is designed.The converter adopts V2COT architecture,and has the characteristics of high output accuracy and fast transient response.An improved adaptive on time control mode is adopted to reduce the influence of load current on switching frequency so that the converter has good switching frequency stability under continuous conduction mode(CCM).Based on 0.15μm BCD process of DB HiTek,the tape-out is carried out.The input voltage is 4.5-17 V,the output voltage is 0.76-7 V,the maximum load current is 3 A,and the switching frequency is 1 MHz.The test results show that the switching frequency varies with the input voltage at a rate of 2.67 kHz/V and with the load current at a rate of 2.95 kHz/A under CCM,the peak efficiency is 96.43%,the output voltage ripple is 8.2 mV,the load adjustment rate is 0.93%,and the load transient response time is less than 20μs.

关 键 词：自适应导通时间 恒定开关频率 降压型DC-DC转换器 低输出电压纹波 

分 类 号：TN432[电子电信—微电子学与固体电子学]