U2405B

U2405B Fast Charge Controller for Drained NiCd/NiMH Batteries Description The fast-charge battery controller circuit, U2405B, uses bipolar technology. The IC enables the designer to create an efficient and economic charge system. The U2405B incorporates intelligent multiple-gradient batteryvoltage monitoring and mains phase control for power management. With automatic top-off charging, the integrated circuit ensures that the charge device stops regular charging before the critical stage of overcharging is achieved. It incorporates an additional algorithm for reactivating fully drained batteries especially after longtime storage. It has two LED driver indications for charge and temperature status. Features D D D D D D D D Preformation algorithm for drained batteries Multiple gradient monitoring Temperature window (Tmin/Tmax) Exact battery voltage measurement without charge Phase control for charge-current regulation Top-off and trickle charge function Two LED outputs for charge status indication Disabling of d2V/dt2 switch-off criteria during battery formation Applications D Portable power tools D Laptop/notebook personal computer D Cellular/cordless phones D Emergency lighting systems D Hobby equipment D Camcorder D Battery-voltage check 18 (20) 17 (19) 16 (18) 14 (15) Package: DIP18, SO20 13 (14) 12 (13) 11 (12) Sync ö C ö R VRef 6.5 V/10 mA Oscillator Status control 3 (3) Phase control Vöi 4 (4) Scan path 1 (1) Trigger output Control unit Gradient d2V/dt2 and...