Features

• Switching Regulator Makes Optimal Use of Limited  Power Available from USB Port to Charge Battery  and Power Application
• 180mΩ Internal Ideal Diode Plus Optional External  Ideal Diode Controller Seamlessly Provides Low  Loss Power Path When Input Power is Limited or  Unavailable
• Full Featured Li-Ion/Polymer Battery Charger
• V_BUS Operating Range: 4.25V to 5.5V (7V Absolute  Maximum—Transient)
• 1.2A Maximum Input Current Limit
• 1.5A Maximum Charge Current with Thermal Limiting
• Bat-Track Adaptive Output Control
• Slew Control Reduces Switching EMI
• Low Profile (0.75mm) 14-Lead 4mm × 3mm DFN Package

Typical Application

Description

The LTC4088 is a high efficiency USB PowerPath controller and Li-Ion/Polymer battery charger. It includes a synchronous switching input regulator, a full-featured battery charger and an ideal diode. Designed specifically for USB applications, the LTC4088’s switching regulator automatically limits its input current to either 100mA, 500mA or 1A for wall-powered applications via logic control.

The switching input stage provides power to VOUT where power sharing between the application circuit and the battery charger is managed. Unlike linear PowerPath controllers, the LTC4088’s switching input stage can use nearly all of the 0.5W or 2.5W available from the USB port with minimal power dissipation. This feature allows the LTC4088 to provide more power to the application and eases thermal issues in space-constrained applications.

An ideal diode ensures that system power is available from the battery when the input current limit is reached or if the USB or wall supply is removed.

The LTC4088 is available in the low profile 14-Lead 4mm × 3mm × 0.75mm DFN surface mount package.