Single-cell charger chip handles more functions

Edited by the Electronicstalk editorial team Mar 25, 2005

The LTC4061 is a compact stand-alone linear single-cell Li-ion battery charger with advanced features to improve charging safety, charge termination and status reporting and prolong battery life.

New from Linear Technology, the LTC4061 is a compact stand-alone linear single-cell Li-ion battery charger with advanced features to improve charging safety, simplify charge termination and status reporting and prolong battery life.

For safety, 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.

Moreover, I/O pins report the state-of-charge during trickle, normal and end-of-charge modes as well as indicate the presence of an AC adapter or faulty battery.

The LTC4061 prolongs battery life by eliminating unnecessary re-charge cycles with its SmartStart feature.

The IC offers four methods for charge termination: user adjustable current and time, external digital control or automatic C/10.

The LTC4061 is housed in a 3 x 3mm DFN package and is ideal for charging a battery from a wall adapter or USB in MP3 players, digital cameras, PDAs and cellphones.

The LTC4061 can charge both 4.2V and the new 4.4V float voltage Li-ion batteries with +/-0.5 and +/-0.35% accuracy, respectively.

It requires no external sense resistor, MOSFET or blocking diode, greatly simplifying design.

In addition, the LTC4061 includes a soft-start circuit to minimise 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 recharge cycles reduce battery capacity and shorten battery life, the SmartStart feature starts recharging the battery only if the battery voltage drops below 4.1V.

This feature reduces the number of unnecessary charge cycles, prolonging battery life.

At any point in the charge cycle, the LTC4061 can be shutdown, limiting battery drain current to less than 2uA.

The LTC4061 is offered in a 10-lead 3 x 3mm DFN package.

1000-piece price starts at $1.95.