Linear 公司的LTC4098 是USB兼容的开关电源管理/锂离子电池充电器，它具有过压保护，USB 端口的负载电流高达700mA，输入电压从5V 到38V，可广泛应用在媒体播放器，数码相机，GPS，PDA和智能手机。本文介绍了LTC4098的主要性能，方框图和典型应用电路，以及多种应用案例。
LTC4098 USB Compatible Switching Power Manager/Li-Ion Charger with Overvoltage Protection
The LTC®4098 is a high efficiency USB PowerPathTM controller and full-featured Li-Ion/Polymer battery charger. It seamlessly manages power distribution from multiple sources including USB, wall adapter, automotive, firewire or other high voltage DC/DC converters, and a Li-Ion/Polymer battery.
The LTC4098’s internal switching regulator automatically limits its input current for USB compatibility. For automotive and other high voltage applications, the LTC4098 interfaces with a Linear Technology external switching regulator to provide a high efficiency high voltage power path. Both the USB and the optional high voltage inputs feature Bat-Track optimized charging to provide maximum
power to the application and ease thermal issues in high power density applications with input supplies from 5V to as high as 38V.
An overvoltage circuit protects the LTC4098 from high voltage damage on the USB/Wall adaptor inputs with an N-channel FET and a resistor.
The LTC4098 is available in the ultra-thin (0.55mm) 20-Lead 3mm 4mm QFN surface mount package.
主要特性：
■ Switching Regulator with Bat-TrackTM Adaptive Output Control Makes Optimal Use of Limited Power Available from USB Port to Charge Battery and Power Application
■ Overvoltage Protection Guards Against Damage
■ Bat-Track External Step-Down Switching Regulator Control Maximizes Efficiency from Automotive, Firewire and Other High Voltage Sources
■ 180mInternal Ideal Diode Plus External Ideal Diode Controller Seamlessly Provide Low Loss PowerPath When Input Power is Limited or Unavailable
■ Full Featured Li-Ion/Polymer Battery Charger
■ “Instant-On” Operation with Discharged Battery
■ 700mA Maximum Load Current from USB Port
■ 1.5A Maximum Charge Current with Thermal Limiting
■ Slew Control Reduces Switching EMI
■ Ultra-Thin (0.55mm) 20-Lead 3mm 4mm QFN
应用：
■ Media Players
■ Digital Cameras
■ GPS
■ PDAs
■ Smart Phones
图1。LTC4098方框图
图2。LTC4098典型应用电路
典型应用电路案例：
1．高效USB/汽车电子充电器
High Efficiency USB/Automotive Battery Charger with Overvoltage
Protection, Reverse-Voltage Protection and Low Battery Start-Up
2．USB/墙上适配器电池充电器
USB/Wall Adapter Battery Charger with Dual Overvoltage Protection,
Reverse-Voltage Protection and Low Battery Start-Up
3．USB/汽车电子电池充电器
USB/Automotive Switching Battery Charger with
Automatic Current Limiting on Both Inputs
4．低成本和汽车电子高效功率管理器
Low Cost USB and Automotive High Efficiency Power Manager with Low Battery Start-Up
本文关键字：电源 电工文摘，电工技术 - 电工文摘
