Linear LTC3576电源管理/充电方案

Linear公司的LTC3576/LTC3576-1是高度集成的功率管理和电传充电器集成电路,每个器件集成高效率双向开关的能自动优先负载的PowerPath管理器,电池充电器,理想二极管,用来控制外接高压开关稳压器的控制器和三个可采用I2C来调整输出电压的通用降压开关稳压器.可广泛用于基于HDD的媒体播放器,GPS,PDA,数码相机和智能手机以及汽车用的手提电子设备.本文介绍了LTC3576/LTC3576-1的主要特性,方框图和典型应用电路以及多种应用电路图.

The LTC3576/LTC3576-1 are highly integrated power management and battery charger ICs for Li-Ion/Polymer battery applications. They each include a high efficiency,
bidirectional switching PowerPath™ manager with automatic load prioritization, a battery charger, an ideal diode, a controller for an external high voltage switching regulator and three general purpose step-down switching regulators with I2C adjustable output voltages. The internal switching regulators automatically limit input current for USB compatibility and can also generate 5V at 500mA for USB on-the-go applications when powered from the battery.
Both the USB and external switching regulator power paths feature Bat-Track optimized charging to provide maximum power to the application from supplies as high as 38V. An
overvoltage circuit protects the LTC3576/LTC3576-1 from damage due to high voltage on the VBUS or WALL pins with just two external components. The LTC3576/LTC3576-1 are
available in a low profi le 38-pin (4mmx6mmx0.75mm) QFN package.

主要特性:
Bidirectional Switching Regulator with Bat-Track™ Adaptive Output Control Provides Efficient Charging and a 5V Output for USB On-The-Go
Bat-Track Control of External High Voltage Step-Down Switching Regulator
Overvoltage Protection Guards Against Damage
“Instant-On” Operation with Discharged Battery
Triple Step-Down Switching Regulators with I2C Adjustable Outputs (1A/400mA/400mA IOUT)
180mΩ Internal Ideal Diode + External Ideal Diode Controller Powers the Load in Battery Mode
Li-Ion/Polymer Battery Charger (1.5A Max ICHG)
Battery Float Voltage: 4.2V (LTC3576), 4.1V (LTC3576-1)
Compact (4mm.6mm.0.75mm) 38-pin QFN Package

应用:
HDD-Based Media Players
GPS, PDAs, Digital Cameras, Smart Phones
Automotive Compatible Portable Electronics



图1. LTC3576方框图



图2. LTC3576典型应用电路



图3.LTC3576应用电路(1)



图4.LTC3576应用电路(2)



图5.LTC3576应用电路(3)



图6.LTC3576应用电路(4)



图7.LTC3576应用电路(5)