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U2402B
Fast Charge Controller for NiCd/NiMH Batteries
Description
The fast-charge battery controller circuit, U2402B, uses bipolar technology. The IC enables the designer to create an efficient and economic charge system. The U2402B 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 has two LED driver indications for charge and temperature status.
Features
D D D D D D D
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
Package: DIP18, SO20
16 (18) 14 (15) 13 (14) 12 (13) 11 (12)
D Battery-voltage check
18 (20) 17 (19)
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 –dV
Battery detection VRef = 5 V 10 (11) VBatt Monitor 0.1 to 4 V
Power - on control
15 (17) 2 (2)
Power supply VS = 8 to 26 V
160 mV Ref
Temp. control Sensor Tmax
Charge break output
94 8585
5 (5)
6 (6)
7 (8)
8 (9)
9 (10) ( ) SO 20, Pins 7 and 16 NC
Figure 1. Block diagram
TELEFUNKEN Semiconductors Rev. A3, 14-Nov-96
1 (17)
U2402B
Pinning
Package: DIP18 Output 1 18 Vsync 17 öC 16 öR 15 V S 14 VRef 13 Osc 12 STM. 11 LED1 10 VBatt
Pin Description
Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Symbol Output GND LED2 Vöi OPO OPI Tmax Sensor tp VBatt LED1 STM. Osc VRef VS ö
R C
GND 2 LED2 Vöi OPO OPI Tmax 3 4 5 6 7
Sensor 8 tp 9
93 7723 e
ö
Vsync. Symbol Output GND LED2 Vöi OPO OPI NC Tmax Sensor tp VBatt LED1 STM. Osc VRef NC VS ö
R C
Function Trigger output Ground Display output “Green” Phase angle control input voltage Operational amplifier output Operational amplifier input Maximum temperature Temperature sensor Charge break output Battery voltage LED display output “Red” Test mode switch (status control) Oscillator Reference output voltage Supply voltage Ramp current adjustment – resistance Ramp voltage – capacitance Mains synchronization input Function Trigger output Ground Display output “Green” Phase angle control input voltage Operational amplifier output Operational amplifier input Not connected Maximum temperature Temperature sensor Charge break output Battery voltage LED display output “Red” Test mode switch (status control) Oscillator Reference output voltage Not connected Supply voltage Ramp current adjustment – resistance Ramp voltage – capacitance Mains synchronization input
Package: SO20 Output 1 20 19 18 17 16 15 14 13 Vsync
GND 2 LED2 Vöi OPO OPI 3 4 5 6
ö ö
C
R
VS NC VRef Osc STM.
NC 7 Tmax 8
Sensor 9 tp 10
94 8594
12 LED1 11 VBatt
ö
Vsync.
2 (17)
TELEFUNKEN Semiconductors Rev. A3, 14-Nov-96
D4
Mains T1 From Pin 15 VS 10 nF C0 13 12 11 1 kW D 7 Red R5 BC 308 R1 D6 10 k W 0.22 mF R0 270 k W R3 R4 C2 14 R Oscillator 16 ϕ VRef 6.5 V/10 mA ϕ 2.2 k W 10 nF 17 Sync C Phase control Vϕ i To Pin 4 1 Trigger output Gradient C1 VS 15 2 Power supply VS = 8 to 26 V 470 mF d2 V/dt 2 & –dV VBatt Monitor 0.1 to 4 V 160 mV Ref 5 6 1 mF CR Temp. control Tmax Sensor 1 mF C4 RT3 24 k W 10 k W C8 0.1 mF 7 8 Control unit Battery detection VRef = 5 V 18 560 k W 2x 560 W R7 1 kW C6 R13 C3 R10 10 W From RT1 / RT2 R8 1 kW D1 R2 0.1 mF 100 k W
D5
TELEFUNKEN Semiconductors Rev. A3, 14-Nov-96
D8 Green R11 R9 10 k W Status control 3 Scan path RB1 1 kW I ch 10 Power on control NTC 4 Charge break output RT1 12 k W To VRef (Pin 14) RT2 100 k W 9 R6
D2
Th1
D3
Th2
RB2
C7
10 k W
4.7 mF 16 k W
Figure 2. Block diagram with external circuit (DIP pinning)
RB3
Battery (4 cells)
DC
160 mV
Rsh
0.2
W
U2402B
94 8674
3 (17)
U2402B
General Description
The integrated circuit, U2402B, is designed for charging Nickel-Cadmium (NiCd) and Nickel-Metal-Hydride (NiMH) batteries. Fast charging results in voltage lobes when fully charged (figure 3). It supplies two identifications ( i. e., + d2V/dt2, and – DV) to end the charge operation at the proper time. As compared to the existing charge concepts where the charge is terminated after voltage lobes according to – DV and temperature gradient identification, the U2402B-C takes into consideration the additional changes in positive charge curves, according to the second derivative of the voltage with respect to time (d2V/dt2). The charge identification is the sure method of switching off the fast charge before overcharging the battery. This helps to give the battery a long life by.