Battery charger takes comparator onboard

Edited by the Electronicstalk editorial team May 5, 2005

The LTC4062 is a compact stand-alone linear single-cell Li-ion battery charger with integrated micropower comparator.

Linear Technology has introduced the LTC4062, a compact stand-alone linear single-cell Li-ion battery charger with integrated micropower comparator.

It offers advanced features for charging safety, increased charge termination flexibility, improved status reporting, and prolonged battery life.

For safety, the LTC4062 is equipped with an adjustable timer for charge termination and a precision float voltage to prevent overcharging of the cell.

To eliminate the risk of overheating while charging at a maximum rate, a patented thermal regulation circuit keeps the LTC4062's junction temperature at a safe level.

Moreover, I/O pins report the state-of-charge during trickle, normal and end-of-charge modes.

The LTC4062 includes an integrated precision, micropower comparator.

This is an undedicated comparator with a general purpose input and open-drain output.

Potential uses include low battery detection or precision input voltage detection.

The LTC4062 prolongs battery life by eliminating unnecessary recharge cycles with its SmartStart feature.

Because frequent recharge cycles reduce battery capacity and shorten battery life, SmartStart operation prevents a new charge cycle from starting if the battery voltage is above 4.1V when power is first applied to the charger.

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

The LTC4062 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 LTC4062 can charge Li-ion batteries to a 4.2V float voltage with +/-0.35% accuracy.

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

In addition, the LTC4062 includes a soft-start circuit to minimise inrush current at the start of a charge cycle.

For USB-powered charging, the logic pin from a USB controller can select low power or high power compliant charge currents, eliminating dependence on external discrete components.

At any point in the charge cycle, the LTC4062 can be shut down, limiting battery current drain to less than 2uA.

1000-piece pricing starts at $1.95 each.