LINEAR Technology, represented in Australia by Soanar , has introduced the LTC4053, a USB compatible linear charger for single-cell Li-Ion/Li-Pol batteries.
This simplifies battery charger design in portable devices, which depend on a host's USB port power for low current charging and a wall adapter power supply for fast charging.
The IC features 7% charge accuracy and can easily be switched from 100mA to 500mA yet can deliver up to 1.25A of constant current when a wall adapter is present.
The LTC4053's unique thermal regulation charges at the maximum rate permitted while preventing overheating of the charger or portable product.
Other linear chargers undergo thermal shutdown for self-protection after overheating, which is potentially harmful to the end device.
As a standalone charger, the LTC4053 does not depend on a microcontroller for charge monitoring, control or termination.
The IC is fully integrated in a 10-lead MSOP package so external MOSFET, sense resistor and blocking diode are unnecessary.
The end products that benefit from the LTC4053 include portable data storage devices, handheld equipment, cell phones, digital cameras, printers and PDAs.