The LTC4098 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.
The LTC4098 is a high‑efficiency USB PowerPath controller and full‑featured Li‑Ion/Polymer battery charger. It manages power from multiple sources—including USB, wall adapters, automotive, FireWire and other high‑voltage DC/DC converters—and provides seamless power distribution to the load and battery. The device includes an internal switching regulator that limits input current for USB compatibility and supports input voltages from 5 V up to about 38 V.
Key features include over‑voltage protection using the OVSENS and OVGATE pins, Bat‑Track optimized charging, an internal ideal diode with external controller, and a compact 20‑lead 3 mm × 4 mm QFN package (0.55 mm height). The datasheet provides detailed electrical characteristics, pin descriptions, typical performance curves, and example application schematics.
| Input Supply Voltage (VBUS) – Typical | 5.5 V |
|---|---|
| Maximum Load Current from USB Port | 700 mA |
| Maximum Charge Current (Thermal Limited) | 1.5 A |
| Operating Temperature Range | –40 °C to 85 °C |
| Maximum Junction Temperature | 125 °C |
| Package | 20‑Lead 3 mm × 4 mm QFN, 0.55 mm height |
| Switching Frequency (typical) | 2.25 MHz |
The device can supply up to 700 mA of load current from the USB port.
It accepts input supplies from 5 V (USB) up to about 38 V for high‑voltage sources such as automotive or FireWire.
The LTC4098 is offered in an ultra‑thin 20‑lead 3 mm × 4 mm QFN package with a height of 0.55 mm.