New Industry Products

LTC Presents New LTC4061 Li-Ion Charger

January 17, 2005 by Jeff Shepard

Linear Technology Corp. (LTC, Milpitas, CA) introduced its new LTC4061, a stand-alone, linear, one-cell lithium-ion (Li-Ion) battery charger with advanced features to improve charging safety, simplify charge termination and status reporting and prolong battery life. The LTC4061 is suitable for charging a battery from a wall adapter or USB in MP3 players, digital cameras, PDAs and cell phones.

The LTC4061 is equipped with a thermistor interface for temperature qualified charging, an adjustable timer as a backup charge termination, and precision float voltage to prevent overcharging of the cell. To eliminate the risk of overheating while charging at maximum rate, a patented thermal regulation circuit keeps the LTC4061's junction temperature at a safe level. The LTC4061 prolongs battery life by eliminating unnecessary re-charge cycles with its SmartStart™ feature.

The LTC4061 can charge both 4.2 V and the new 4.4 V float voltage Li-Ion batteries with ±0.5% and ±0.35% accuracy, respectively. It requires no external sense resistor, MOSFET or blocking diode. The LTC4061 includes a soft-start circuit to minimize the inrush current at the start of a charge cycle. For USB powered charging, the logic pin from a USB controller can select the charge current, eliminating dependence on external discrete components. After a battery is fully charged, the LTC4061 enters a standby mode. Because frequent re-charge cycles decrease battery capacity and shorten battery life, the SmartStart feature starts re-charging the battery only if the battery voltage drops below 4.1 V. At any point in the charge cycle, the LTC4061 can be shut down, limiting battery drain current to less than 2 µA.

The LTC4061 is offered in a 10-lead, 3 mm x 3 mm DFN package. Pricing for 1,000-piece quantities starts at $1.95.