LTC3801B中文资料Micropower Constant Frequency Step-Down DC/DC Controllers in ThinSOT数据手册ADI规格书

描述 Description

The LTC®3801/LTC3801B are constant frequency current mode step-down DC/DC controllers in a low profile (1mm max) 6-lead SOT-23 (ThinSOT™) package. The parts provide excellent AC and DC load and line regulation with ±1.5% output voltage accuracy. The LTC3801 consumes only 195mA of quiescent current in normal operation, dropping to 16µA under no-load conditions.
The LTC3801/LTC3801B incorporate an undervoltage lockout feature that shuts down the device when the input voltage falls below 2.2V. The LTC3801 automatically switches into Burst Mode operation at light loads which enhances efficiency at low output current. In the LTC3801B, Burst Mode operation is disabled for lower output ripple at light loads.
To further maximize the life of a battery source, the external P-channel MOSFET is turned on continuously in dropout (100% duty cycle). High switching frequency of 550kHz allows the use of a small inductor.

特性 Features

·High Efficiency: Up to 94%
·Very Low No-Load Quiescent Current: Only 16µA (LTC3801)
·High Output Currents Easily Achieved
·Internal Soft-Start
·Wide VIN Range: 2.4V to 9.8V
·Low Dropout: 100% Duty Cycle
·Constant Frequency 550kHz Operation
·Burst Mode® Operation for High Efficiency at Light Loads (LTC3801)
·Burst Mode Operation Disabled for Lower Output Ripple at Light Loads (LTC3801B)
·Output Voltage as Low as 0.8V
·±1.5% Voltage Reference Accuracy
·Current Mode Operation for Excellent Line and Load Transient Response
·Only 6µA Supply Current in Shutdown (LTC3801)
·Low Profile (1mm) SOT-23 Package

应用 Application

·1- or 2-Cell Li-Ion Battery-Powered Applications
·Wireless Devices
·Portable Computers
·Distributed Power Systems

简介

LTC3801B属于集成电路（IC）的PMIC-稳压器-DCDC开关式控制器。由ADI制造生产的LTC3801BDC-DC 开关控制器PMIC（电源管理集成电路）DC 到 DC 开关式控制器是用于高效率电路的稳压 IC，其配置为生成高于（突升或步升）或低于（突降或步降）输入电源的输出电源电压。其他拓扑结构可能包括：降压-升压、反激、正激、Cuk、SEPIC、全桥、半桥和推挽式。这些器件不同于需要最小电压并“烧尽”多余电压的线性稳压器。