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U2407B
Simple Controller for Fast Charge Systems
Description
The bipolar IC U2407B is a fast charge battery controller for drained NiCd/ NiMH batteries. Apart from phase control, it is identical with U2405B, but has four LED outputs. The IC enables the designer to create an efficient and economic charge system. The U2407B incorporates an intelligent multiple-gradient battery-voltage monitoring combined with temperature and failure mode detection. 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 long time storage. It has four LED driver outputs for different indications of the charge status.
Features
D D D D D D D D
Multiple gradient monitoring Temperature window (Tmin/Tmax) Exact currentless measurement Four LED status outputs Linear power control Preferred for externally regulated current sources Preformation algorithm for drained batteries Programmable top-off charge function
Applications
D Primary switch mode D AC/ DC wall plug adapter D Ultra fast charger (10 minutes)
Package: DIP16/ SO16
13
12
15
2
3
10
VRef 6.5 V/10 mA
Oscillator Status control Scan path 11
16
Switch output
Control unit
Gradient d2V/dt2 and –dV Battery detection VRef = 5 V 9 VBatt monitor 0.1 to 4 V
Power - on control
14 1
Power supply VS = 8 to 26 V
160 mV Ref
Tmax
Temp. control Sensor
Charge break output
95 10648
4
5
6
7
8
Figure 1. Block diagram
TELEFUNKEN Semiconductors Rev. A4, 05-Mar-97
1 (16)
U2407B
10 W Input Voltage 8 V to 24 V C10 10 mF R7 1 kW R1 R4 2.2 kW R5 2.2 kW LED1 LED2 BD649 Mounted on heatsink D1 BYW52 T1 T2 RB1 1 kW RB2 10 kW RB3 10 kW Battery LED3 LED4 BC237 R8 100 kW CR 1 mF VBatt C7 1 mF 7 Sensor 9 6 16 12 R6 Rsh 0.2 W 10 kW C4 1 mF OPI 5 8 tp 11 STM Tmax Output Osc CO 10 nF RT2 100 kW RT3 1.5 kW RO 270 kW OPO VS 10 2 3 15 4 C2 0.22 mF 14 1 C1 220 mF GND
U2407B
13
VRef
Ich
95 10677
Figure 2. Scheme for DC linear regulation
Pin Description
Package: DIP16/ SO16 GND LED2 LED3 OPO OPI Tmax 1 2 3 4 5 6 16 Output 15 LED4 14 VS 13 VRef 12 Osc 11 STM 10 LED1 9
95 10618
Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Sensor 7 tp 8
VBatt
Symbol Function GND Ground LED2 Display output “top-off/ trickle charge” LED3 Display output “Fast charge” OPO Operational amplifier output OPI Operational amplifier input Tmax Maximum temperature Sensor Temperature sensor tp Charge break output VBatt Battery voltage LED1 Display output “failure mode” STM. Test mode switch (status control) Osc Oscillator VRef Reference output voltage VS Supply voltage LED4 Display output “top-off charge” Output Trigger output
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TELEFUNKEN Semiconductors Rev. A3, 05-Mar-97
U2407B
General Description
The integrated circuit, U2407B, is designed for charging Nickel-Cadmium (NiCd) and Nickel-Metal-Hydride (NiMH) batteries. Fast charging results i.