Linear Technology Corp. (LTC, Milpitas, CA) introduced the LTC4056, a linear, lithium-ion, battery charger controller in a ThinSOT™ package that provides a microcontroller-free solution, as well as faster charging from a poorly regulated or a sagging input supply such as a wall adapter or USB port. The total solution occupies an area of less than 75mm² and has a height of 1mm allowing it to fit in the tight space requirements of portable hand-held devices.
The LTC4056 continues charging the battery by limiting the charge current until the input power source recovers when competing ICs inhibit charging or pull down on an input power supply when the input-voltage source sags. As a result, the LTC4056's uninterrupted battery charging reduces the charging time. Moreover, the IC includes all the necessary functions for charging, charge termination and protection. End products include MP3 players; digital cameras; PDAs; cell phones; headsets; and USB-interfaced, battery-powered electronics.
The LTC4056 targets systems that need to charge a 4.2V lithium-ion battery from a 4.5V to 6.5V input source with charge currents ranging from 200mA to 700mA. To reduce the solution cost, the LTC4056 eliminates the need for an input reverse current blocking diode and a sense resistor. Precision one-cell, lithium-ion battery charging is guaranteed with a preset 4.2V, ±0.5 percent accurate float voltage. The LTC4056 also features automatic recharge, charge conditioning, status output signal and ac adapter detection. The LTC4056 drives a PNP transistor for providing current to the battery.
Pricing starts at $1.35 each in 1,000-piece quantities.
