一种超低静态电流ACOT降压转换器  

Ultra-Low Quiescent Current ACOT Step Down Converter

作　　者：汪东 谢凌寒 WANG Dong;XIE Linghan(Wuxi Etek Micro-Electronic Co.,Ltd.,Wuxi 214028,China)

机构地区：[1]无锡力芯微电子股份有限公司,江苏无锡214028

出　　处：《电子与封装》2023年第9期34-40,共7页Electronics & Packaging

摘　　要：在可穿戴和物联网等应用领域,电池通常为系统供电。为保证系统能长时间待机,需要电源芯片具有超低待机电流。为降低待机功耗,在空载进入休眠模式时关断大部分电路,仅保留低功耗振荡器(LP_OSC)、电压基准的采样保持电路和低功耗比较器(LP_CMP),待机电流仅为430nA。为保证良好的负载瞬态响应,设计了自适应恒定导通时间(ACOT)架构。该架构具有瞬态响应好、电流连续模式频率稳定、环路稳定性好等特点。该芯片可提供最大600mA的负载电流,峰值效率可达96%,在输入电压为5V、输出电压为3.3V、带载电流为10μA时,效率大于80%。In the applications such as wearable and internet of things(IOT),the system is usually powered by batteries.In order to ensure a long standby time,the power supply chip is required to have an ultra-low standby current.In order to reduce standby power consumption,most circuits turn off in sleep mode with no load,and only low power oscillator(LP_OSC),voltage reference sample&hold and low power comparator(LP_CMP)work,so the standby current is merely 430 nA.Meanwhile,in order to ensure good transient performance,an adaptive constant on time(ACOT)structure is designed.This structure has the characteristics of good transient performance,stable frequency in current continuous mode and stable loop.The chip can deliver as much as 600 mA current for output,and the peak efficiency is up to 96%.With 5 V input voltage,3.3 V output voltage and 10μA current load,the efficiency is higher than 80%.

关 键 词：降压转换器 超低静态电流 自适应恒定导通时间 轻载高效率 

分 类 号：TN433[电子电信—微电子学与固体电子学]