DESCRIPTION

The LTC®4126 is a low-power wireless single-cell Li-Ion battery charger with an integrated step-down DC/DC regulator. The step-down regulator is a low-noise multi-mode charge pump which is powered from the battery and provides a regulated 1.2V at the output. The switching frequency is set to either 50kHz or 75kHz depending on the mode to keep any switching noise out of the audible range.

FEATURES

■ Wireless Li-Ion Battery Charger Plus High

Efficiency Multi-Mode Charge Pump DC/DC

■ Wideband Rx Frequency: DC to >10MHz

■ Integrated Rectifier with Overvoltage Limit

■ Pin Selectable Charge Voltage: 4.2V or 4.35V

■ Charge Current: 7.5mA (Fixed)

■ Low Battery Disconnect: 3.0V

■ NTC Pin for Temperature Qualified Charging

■ DC/DC Regulated Output: 1.2V

■ DC/DC Output Current: Up to 60mA

■ 50kHz/75kHz Switching, No Audible Noise

■ Pushbutton and/or Digital on/off Control for DC/DC

■ Thermally Enhanced 12-Lead 2mm × 2mm

LQFN Package

APPLICATIONS

■ Hearing Aids

■ Low Power Li-Ion Powered Devices

■ Wireless Headsets

■ IoT Wearables