July 20, 2004

By: Edgar Wittal
Website: http://www.1st-in-batteries.com

Semtech Launches Miniature Battery Charger ICs with Redundant Charge Termination

Semtech Corp., a leading supplier of analog and mixed-signal semiconductors for communications, portable devices, computers, and industrial equipment, today announced availability of the SC802 series of Lithium-ion/Lithium-polymer battery charger ICs.

The two new devices feature a six-hour programmable charge timer and thermistor voltage input sensor to allow designers to program in redundant charge termination functions to protect portable products from faulty batteries.

Portable designers are looking at all aspects of their power systems to improve safety, and they increasingly want charge termination redundancy built into their products to ensure that overcharging isn’t the cause of battery safety issues, said Eddie Yeow, Vice President of Semtech’s Portable Products Group.

With the SC802 we give designers two types of redundancy without sacrificing the small size and strong features for which Semtech battery charging solutions are known.

Portable product designers can program the SC802 charger to automatically terminate charging after any length of time, up to six hours. The IC’s thermistor input sensor can read voltage changes that indicate changing thermal conditions and can terminate charging when these conditions are outside programmed ranges.

Like all of Semtech’s battery charger ICs, the SC802 chargers automatically detect the voltage levels in a battery and will initiate either a pre-charge current for deeply discharged batteries with less than 2.8 volts of power, or fast-charge current for batteries with power levels higher than 2.8 volts.

Once a battery reaches 70% of capacity, the current is reduced while the voltage remains constant until the battery is fully charged. Once charging is complete, the SC802 goes into a maintenance mode to ensure that the battery remains at full capacity while a charging adapter is connected.

The SC802 features a 14V input voltage range that eliminates additional protection circuitry required by other 5V chargers in the event of faulty adapters. The SC802 also provides an LDO mode that can be used to power the device directly from the power adapter when the battery is removed.

The SC802 is available in an optional, lead-free 4mm by 4mm footprint, 0.9mm height micro-leaded package that is ideal for use in cell phones, smart phones, charger stations and personal digital assistants.

The SC802 chargers join the SC801 and SC803 charger families of miniature battery charger ICs for portable designs.

All of Semtech’s battery charger ICs combine controller, thermally protected power MOSFET, reverse-blocking diode, and sense resistor-elements that comprise a complete charging management system.

The device's packaging provides efficient heat dissipation to promote optimal system performance in a very small PCB area. This feature combination allows engineers to cut cost, board space, and design effort over competing solutions. For more information, see .

About The Author:

Edgar Wittal is a successful author and regular contributor to http://www.1st-in-batteries.com.  A great resource for batteries of all kinds including camcorder, laptop, cell phone and more.