Outline

This IC provides protection for lithium ion batteries in the event of overcharging, overdischarging and overcurrents. When anomalies occur during charging or at other times and excessive voltages are applied, after a certain time has elapsed for each cell an external FET switch is turned off (overcharging detection); and in order to prevent overdischarge of the battery during discharge, when the voltage of individual batteries falls below a fixed voltage, an external FET switch is turned off (overdischarge detection), and the IC is put into low-consumption current mode. When large currents flow due to a short-circuit or other cause, an external MOS switch is turned off (overcurrent detection).

Features

1. Current consumption (overcharging)              VCELL > VCELLU          170µA typ.

2. Current consumption (normal operation)        VCELL < VALM            35µA typ.

3. Current consumption (overdischarge)             VCELL < VCELLS          0.1µA max.

4. Overcharge detection voltage (-20 to +70°C)   VCELL : L -> H          4.25V±50mV/CELL

5. Overcharge hystereis voltage                        VCELL : H -> L          VCELLU-200mV/CELL typ.

6. Overcharge sensing dead time                     C=0.1µF                 1.0S typ.

7. Overcharge sensing operation voltage           VCELL : L -> H          4.10V±150mV/CELL

8. Overdischarge detection voltage                  VCELL : H -> L          2.40V/CELL typ.

9. Overdischarge sensing dead time                 C=0.1µF                 1.0S typ.

10.Overcurrent detection voltage                     0.15V typ.

11.Overcharge and overdischarve voltages as well as the overcurrent detection voltage can be changed upon request.

Applications

  Lithium ion battery pack for notebook computers