Feature-rich battery chargers minimise external components

Freescale Semiconductor has introduced a set of battery-charger ICs supporting multiple modes including trickle charging, constant-current charging at up to 1.2A, and constant-voltage charging at 4.2V. Sophisticated end-of-charge control is also provided, to prolong battery lifetime.

The MC34671, MC34673 and MC34674 are single-input autonomous charging controllers suitable for charging Li-ion or Li-polymer batteries in a variety of handheld and portable applications. The chargers have high inputvoltage ratings, which save the need for input over-voltage protection circuitry when connected to a USB-port power source or AC/DC power adapter.

The MC34674 is optimised for travel-charger applications, featuring smart-battery connection verification to prevent charging if no battery is connected, as well as a dual-colour LED driver with integrated resistors to save external components. All three devices allow a complete battery charger to be implemented without requiring external MOSFETs, blocking diodes or currentsense resistors.

Further common features include support for trickle charging for a deeply discharged battery, an internal timer for termination to prevent charging a failed battery, and charger-current thermal foldback to maximise charge current under spaceconstrained applications without specific thermal design.

 

FEATURES ±0.7% voltage accuracy Die-temperature monitoring Charge current set by external resistor: 600mA (MC34671) 1.2A (MC34673) 1.05A (MC34674) 2mm x 3mm x 0.65mm UDFN package

APPLICATIONS Point of Sale (POS) terminals Bluetooth equipment Field test equipment Data loggers Consumer electronic products

 

 

 

Development board KIT3467xEPEVBE will soon be available to members of the Future Board Club. To apply for the development board, and membership of the Board Club, go to www.my-boardclub.com/manf-offers.htm This offer is free and subject to qualification.

 

Freescale MC34671/3/4 Battery Chargers