Applications LED READY = READY LED READY LED. Charge mode indicator. max 140 C Shunt Sense Osc. Figure 1 Block diagram with external circuit

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1 Charge Timer Description The molithic integrated bipolar circuit is a time controlled constant current charger. Selection of charge current versus timing is according to external components at pins 2, 3 and 4. For high current requirement, an external transistor is recommended in series with the battery. To protect the IC against high power loss (typically > 140 C), the oscillator is shut down Features Easy to run automous dual rate charger Constant charge current 3 h 24 h charge time programmable Integrated low cost dc regulator Integrated overtemperature protection Selectable charge mode indication Operation starts at the moment of battery insertion Final assembly test ability when the reference voltage is switched off (0 ). The same thing happens when there is a saturation of collector voltage at pin 1. When the overtemperature is reduced and the collector voltage is equal to supply voltage ( C = S ), charge time operation continues (see flow chart figure 4). Applications Cordless telephones Low cost battery charger- timer Entertainment Block Diagram LED Ch = Charge (Ch) mode LED READY = READY R C Power supply AC/DC Battery inserted LED Ch R 5 LED LED READY S 8 6 GND Charge mode indicator Power supply S = 3.5 to 12 Test mode 5 S TM max 140 C Timer and control logic Ref = 1.5 /0.1 /0 C 1 + Ref RC oscillator Shunt Sense Osc R R 4 3 C 4 Figure 1 Block diagram with external circuit Rev. A1: (11)

2 TELEFUNKEN Semiconductors Pin Description C 2 SENSE OSC LED GND S S TM Pin Symbol Function 1 C Collector terminal 2 2 Emitter shunt terminal 3 SENSE Amplifier SENSE input 4 OSC Oscillator input 5 S TM Test mode switch 6 S Supply voltage 7 GND Ground 8 LED Charge mode indicator Pin 1, Collector oltage C Terminal Pin 1 is an open collector output. When C 3, the charge cycle is switched off until it is above the supply voltage. The first eight divider stages can be tested directly. 256 input clocks at pin 4 create one clock at pin 5. Pin 2, Emitter Shunt Terminal The constant current source is supplied by the internal operational amplifier. The voltage across R 3 is determined via the internal reference source. I Ch = 3 /R 3 ( 3 = SENSE ) Pin 3, Operational Amplifier SENSE Input (Inverted) The voltage regulated current source has a closed loop with pin 2, pin 3, and resistor R 3. Pin 4, Oscillator Terminal (R 4 /C 4 ) Selection of current charge versus timing is according to the external circuit at pins 2, 3, and 4. Typical values are given in figure 3 and table page 3. Pin 5, Fast Test Mode for Charging Time Charging time is given by the operation. t ch 1 f OSC 2 n where: f osc = oscillator frequency (see figure 3) t ch = charge time n = frequency divider n = 2 26, if S TM = OPEN n = 2 17, if S TM = GND n = 2 8, if S TM = C Pin 4 Pin 5 Oscillator Pulse Test Mode Figure 2 Quick test timer 1/3 Example Assume a charge time of 6 h. Select the values of R 4 and C 4 from the tables on page 3. R 4 = 470 k C 4 = 680 pf There is a frequency of about 3100 Hz at pin 4. It is possible to test the charge time of 6 h by running through the charge cycle for a very short time. By connecting pin 5 with GND the test time is 42 s. By connecting pin 5 with pin 1 ( c ) the test time is reduced to about 82.4 ms. R 5 is connected in parallel to the red LED and provides a protective bypass function for the LED (see figure 1). Pin 6, Supply oltage, S S 3.1 power-on reset release (turn-on) S 2.9 undervoltage reset S 13 supply voltage limitation Pin 7, Ground Pin 8, Charge Mode Indicator It is an open-collector output, which supplies constant current to LED after the active charge phase has been terminated. max controls the function temperature to the final stage range, when the temperature is above 140 C, charge function is switched off. 2 (11) Rev. A1:

3 Charge Characteristics Charge Time Charge ttme Test = OPEN OSC Components R 4 C 4 [K] [pf] Frequency [Hz] Short Test Cycle Test = C [ms] Test = GND [s] 1 h h h h h h h h h min h min h min h min Charge Time Test Mode Open GND C f osc n = 26 n = 17 n = 8 1 KHz 18 h, 38 min 2 min, 11 s 256 ms 10 KHz 1 h, 51 min 13 s 25 ms 100 KHz 11 min, 11 s 1.3 s 2.5 ms Trickle Charge The trickle charge starts after the charge has been terminated. In this case the internal reference voltage is reduced from 1.5 up to about 0.1. This means the charge current is decreased by the factor K = 15 {K = 1.5 /0.1 }. Trickle current = I Ch / 15 + I 6 (supply current) + I 8 With resistor R 6 it is possible to reduce the trickle charge. See figure 7 and 8. f ( Hz ) R t =160k R t =330k R t =680k R t =1100k Figure 3 C t ( pf ) R t =82k Oscillator Rev. A1: (11)

4 TELEFUNKEN Semiconductors Battery inserted Turn on S > 3.5 Sense = 1.5 LED Ch ON Timer START S TM open GND mode S Divider T j > T max C > 2.7 Sense = 40 m interrupt charging LED Ch OFF Hold on timing T j > T max C > S Sense = 1.5 Continious charging LED Ch ON Continious timing End of timing LED Ch OFF LED READY ON Trickle charge mode Sense = 80 m Battery removed Undervoltage reset Figure 4 Flow chart 4 (11) Rev. A1:

5 Absolute Maximum Ratings Reference point Pin 7 (GND), unless otherwise specified. 20 Parameters Symbol alue Unit Supply current Pin 6 I S t 100 s is 100 Currents Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 8 I 1 I 2 I 3 I 4(osc) I TM I to A A oltages Pins 1, 3, 5, 6 and 8 Pin 2 Pin 4 Junction temperature T j 150 C Ambient temperature T amb 85 C Storage temperature range T stg 50 to +150 C Thermal Resistance Parameters Symbol alue Unit Junction ambient R thja DIP 8 SO 8 on PC-board SO 8 on ceramic SO 8 on ceramic with thermal compound K/W K/W K/W K/W Rev. A1: (11)

6 TELEFUNKEN Semiconductors Electrical Characteristics S = 6, T amb = 25C, reference point pin 7 (GND), unless otherwise specified. Parameters Test Conditions / Pins Symbol Min. Typ. Max. Unit Supply voltage limitation Pin 6 S I S = 4 I S = Supply current S = 6 I S oltage monitoring Pin 6 Turn-on threshold TON Turn-off threshold TOFF Charge-mode indicator (LED) Pin 8 LED current I LED saturation voltage I 8 = m Leakage current I lkg A Collector terminal Pin 1 Open collector current I CO A Saturation threshold sat(on) sat(off) Shunt emitter current R 3 = 5.6 Pin 2 I Operational SENSE amplifier Pin 3 Input current SENSE = 0 I A Input voltage Ref = 1.5 Ref = 100 m Ref = m m Oscillator Pin 4 Leakage current 4 = 0 to 0.85 I lkg A Threshold voltage Upper T(u) m Frequency R 4 = 160 k, C 4 = 2.2 nf R 4 = 680 k, C 4 = 4.7 nf Test mode switch (S TM ) Pin 5 Input current 5 = 6 5 = 0 Output voltage High Low f osc I H 1.7 L Hz Hz 6 (11) Rev. A1:

7 Internal Temperature Switch The internal temperature monitoring is active, if the chip temperature rises above 140 C. Above this temperature the voltage at pin 3 goes to zero. Similarly the charge current, I Ch, reduces according to the relation: I Ch = SENSE / R 3 where I Ch = 1 to 2 (IC supply current) The oscillator is connected to GND via pin 3 ( SENSE ) which holds the present time status. When the chip temperature decreases below the transition value, all the functions are released and the charge time is continued. The process is reversible. If there is a higher power dissipation in the circuit (T j > 140 C) the temperature monitoring remains permanently activated (ON). The total cycle time is prolonged according to the interrupt time duration, see figure 5. Automatic Control Protection To reduce the design costs, it is possible to select the transformer for the minimum of the power supply required. The output stage of the control is selected so that it is switched off before saturation is attained ( CEsat = 2.7 ). In this case the voltage at pin 3 is kept at a value of zero. The charge current is also zero, and the transformer is w an open circuit impedance. The system becomes active again if c S. The advantage of the system is that if sags of duration appear in the mains voltage or if the transformers used are too small, the charge duration is increased while the charge capability remains the same (see figure 6) T j 140 C 130 C T j Charge current I C Timing Charge mode Counting timer t Figure 5 Charge duration in case of overtemperature C < S S 2.7 C 0 Charge current I C Timing Charge mode Counting timer t Figure 6 Charge duration in case of C Rev. A1: (11)

8 Application Notes Minimal Configuration Basic Example NiCd battery 750 h R = 510, 1/8 W Charging time: 3 h C=47F16 F, Charge current: R 3 = 6.2, 1/2 W 240, 1/3 C R 4 = 300 k Trickle charge: C 19 < 1/40 C 4 = 470 pf R 5 = 8.2, 1/2 W Basic Equations TELEFUNKEN Semiconductors R = 0.5 / IS IS = 1.8, typically R 5 = _LED Ch / (I Ch 20 ) Charge Current (I Ch ): I Ch = SENSE /R 3 SENSE = 1.48, typically Trickle Current (IT): I Ch = SENSE /R 3 + ILED + IS SENSE = 80 m, typically ILED = 4.5, typically Minimum Supply oltage No of Cells 1 2 DC Supply Minimum DC supply READY Ch R C R Special Requirements of Different Charge Times R 4 2 h 4 h 6 h 7 h 12 h R k 430 k 470 k 470 k 390 k C pf 470 pf 680 pf 1 nf 2.2 nf R 3 C 4 Special Requirements for Different Charge Current R 3 R Figure 7 Standard application 8 (11) Rev. A1:

9 with Booster and Trickle Charge Reduction Basic Example NiCd battery 1000 h Charging time: 2 h Charge current: 500 Trickle charge: 22 < 1/22 C Minimum Supply oltage R = 510, 1/8 W C = 100 F, 16 R 3 = 3, 1 W R 4 = 300 k C 4 = 330 pf R 5 = 3.9, 1 W C 1 = 1 F Basic Equations R = 0.5 / IS R 5 = _LED Ch / (I Ch 20 ) Charge Current (I Ch ) I Ch = SENSE / R 3 SENSE = 1.48, typically Trickle Current (IT) I Ch = SENSE /R 3 + ILED + IS I6 SENSE = 80 m, typically ILED = 4.5, typically IS = 1.8, typically Trickle Charge Reduction (I6) I6 = ( battery + D1 )/R6 D1 = 0.75 No of Cells 1 2 DC Supply Minimum DC supply BYW52 D 1 R C R 6 READY S1 Special Requirements for Different Charge Times C 1 2 h 4 h 6 h 7 h 12 h R k 430 k 470 k 470 k 390 k C pf 470 pf 680 pf 1 nf 2.2 nf BD 136 or BC Special Requirements for Different Charge Current R 3 R R 5 Ch S1: use for test only R3 R 4 C 4 R 6 = 560, reduce trickle charge Figure 8 Application for charge current > 250 Rev. A1: (11)

10 TELEFUNKEN Semiconductors Dimensions in mm Package: DIP Package: SO (11) Rev. A1:

11 Ozone Depleting Substances Policy Statement It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are kwn as ozone depleting substances (ODSs). The Montreal Protocol (1987) and its London Amendments (1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. arious national and international initiatives are pressing for an earlier ban on these substances. TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2. Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency (EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C (transitional substances) respectively. TEMIC can certify that our semiconductors are t manufactured with ozone depleting substances and do t contain such substances. We reserve the right to make changes to improve technical design and may do so without further tice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D Heilbronn, Germany Telephone: 49 (0) , Fax number: 49 (0) Rev. A1: (11)