
Linear Technology
DESCRIPTION
The LTC®1325 provides the core of a flexible, cost-effective solution for an integrated battery management system. The monolithic CMOS chip controls the fast charging of nickel-cadmium, nickel-metal-hydride, lead-acid or lithium batteries under microprocessor control. The device features a programmable 111kHz PWM constant current source controller with built-in FET driver, 10-bit ADC, internal voltage regulator, discharge-before-charge controller, programmable battery voltage attenuator and an easy-to-use serial interface.
FEATURES
■ Fast Charge Nickel-Cadmium, Nickel-Metal-Hydride,
Lithium Ion or Lead-Acid Batteries under µP Control
■ Flexible Current Regulation:
– Programmable 111kHz PWM Current Regulator
with Built-In PFET Driver
– PFET Current Gating for Use with External Current
Regulator or Current Limited Transformer
■ Discharge Mode
■ Measures Battery Voltage, Battery Temperature and
Ambient Temperature with Internal 10-Bit ADC
■ Battery Voltage, Temperature and Charge Time
Fault Protection
■ Built-In Voltage Regulator and Programmable
Battery Attenuator
■ Easy-to-Use 3- or 4-Wire Serial µP Interface
■ Accurate Gas Gauge Function
■ Wide Supply Range: VDD = 4.5V to 16V
■ Can Charge Batteries with Voltages Greater Than VDD
■ Can Charge Batteries from Charging Supplies Greater
Than VDD
■ Digital Input Pins Are High Impedance in
Shutdown Mode
APPLICATIONS
■ System Integrated Battery Charger