Li-ion Battery Chargers Deliver Up To 2 A In Compact Package

A pair of compact, monolithic high-voltage battery chargers for single-cell Li-ion/polymer batteries employ a switch-mode architecture that minimizes power dissipation without compromising board space. The LT3650-4.1 and LT3650-4.2 operate from 4.75 V to 32 V and have a 40-V absolute maximum rating for added system margin. Their user-selectable timer or C/10 termination requires no external microcontroller and simplifies the design. Charge current is programmable and dynamically adjustable up to 2 A. The power device is integrated on chip to save board space. The devices do not require external high-precision resistors to set the float voltage, further saving cost and space. Applications include industrial handheld instruments, 12- to 24-V automotive and heavy equipment, desktop cradle chargers and small notebook or tablet computers. The LT3650-4.1 offers a 4.1-V battery float voltage, allowing high temperature safety margin, while the LT3650-4.2 features a 4.2-V final charge voltage for optimized battery run time. The chargers come in a compact, low-profile (0.75 mm) 12-pin 3- by 3-mm DFN package, and are offered in both E and I grade versions, both operating from ?40°C to 85°C. Pricing starts at $2.80 and $3.22, for the E and I grades respectively, in 1000-piece quantities. LINEAR TECHNOLOGY CORP., Milpitas, CA. (408) 432-1900.