U2403B Charge Timer Description The U2403B is a monolithic, integrated-bipolar circuit which can be used in applications for time-controlled, constant-current charge. Selection of charge current versus timing is carried out by using the external circuit 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 when the reference voltage is switched off (0 V). The latter also takes place when there is a saturation caused by collector voltage at Pin 1. When the overtemperature has disappeared and the collector voltage at Pin 1 has exceeded the supply voltage (V1 > VS), charge time operation continues (see flow chart in figure 3). Features Applications D D D D D D D D D Cordless telephones D Low-cost battery-charge timer D Entertainment Easy-to-run autonomous dual rate charger Constant charge current 3 h – 24 h charge time programmable Low cost dc regulator Overtemperature protection Charge-mode indication Operation starts at the moment of battery insertion Fast charge time-test mode Package: DIP8, SO8 Block Diagram C1 R1 Power supply AC/DC LED2 Battery inserted LED1 R5 Charge Ready LED VS Charge mode indicator í max 140°C GND 94 8629 7 6 8 Power supply 5 Test mode VS = 3.5 to 12 V STM Timer and control logic VRef = 1.5 V/ 0.1 V/ 0 V VRef 1 í V1 + – RC oscillator 3 2 Shunt 4 Sense R3 Osc R4 C4 Figure 1. Block diagram with external circuit TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 1 (12) U2403B Pin Description V1 1 8 LED V2 2 7 GND Sense 3 6 VS Osc 4 5 STM Pin 1 2 3 4 5 6 7 8 Symbol V1 V2 V3 Osc STM VS GND LED Function Collector terminal Shunt emitter terminal Amplifier sense input Oscillator input Test mode switch Supply voltage Reference point, GND Charge mode indicator 94 8685 Pin 1, Collector Voltage V1 1 2 Pin 1 is an open collector output. When V1 ≤ 3 V, the charge cycle is switched off until it is above the supply voltage, as shown in figure 6. 3 256 Pin 4 Oscillator Pin 5 Test – Mode Pulse Pin 2, Shunt Emitter The constant current source is supplied by the internal operational amplifier. The voltage across R3 is determined via the internal reference source. Ich = V3/R3 (V3 = Vsense) Pin 3, Amplifier Sense Input (Inverted) The voltage-regulated current source has a closed loop at Pin 2, Pin 3, and resistor R3. Pin 4, Oscillator Input R4, C4 Selection of current charge versus timing is carried out by using the external circuit at Pins 2, 3, and 4. Typical values are given in charge characteristics (see table next page). Pin 5, Test-Mode Switch for Charging Time The charging time, tch, is given by the following equation. t ch + f1 2n osc where: fosc = oscillator frequency (see figure 2) n = frequency divider = 26, if STM open = 17, if STM = GND = 8, if STM = VS The first eight divider stages can be tested directly. 256 input tact signals at Pin 4 create one tact signal at Pin 5. 2 (12) 94 8839 Figure 2. Quick test timer 1/3 Example Assume a charge time of 6 h. Select the values of R4 and C4 from the tables next page. For example: R4 = 470 kW C4 = 680 pF There is a frequency of approximately 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 (V1), the test time is reduced to about 82.4 ms. R5 is connected in parallel to the LED2 and provides a protective bypass function for the LED (see figure 1). Pin 6, Supply Voltage, VS VS VS VS [ 3.1 V [ 2.9 V [ 13 V power-on reset release (turn-on) under-voltage reset supply voltage limitation Pin 7, Ground TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96 U2403B Pin 8, Charge Mode Indicator Trickle Charge An open-collector output supplies constant current to LED1 after the active charge phase has been terminated. ímax controls the function temperature for the final stage range. This is when the temperature is above 140°C and the charge function is therefore switched off. The trickle charge starts after the charge has been terminated. In this case, the internal reference voltage is reduced from 1.5 V to approximately 0.1 V. This means the charge current is decreased by the factor: K = 1.5 V/ 0.1 V = 15. Trickle current = Ich / 15 + I6 (supply current) + I8 It is possible to reduce the trickle charge with resistor R6, as shown in figures 6 and 7. Charge Characteristics Charge Time Open 3h Test time/ Test-Mode Switch STM VS GND 41.2 ms 21 s 4h 54.9 ms 28 s 5h 68.6 ms 35 s 6h 82.4 ms 42 s 7h 96.1 ms 49 s 8h 109.8 ms 56 s 9h 123.6 ms 1 min 3 s 10 h 137.3 ms 1 min 10 s 12 h 164.8 ms 1 min 24 s 16 h 219.7 ms 1 min 56 s TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 Oscillator Components R4 (KW) C4 (pF) 510 270 430 330 300 470 620 330 430 470 300 680 510 470 390 680 300 1000 620 470 470 680 360 1000 560 680 430 1000 220 2200 620 680 470 1000 200 2200 750 680 510 1000 240 2200 620 820 270 2200 130 4700 390 2200 150 4700 470 2200 200 4700 Frequency fosc (Hz) 6213 4660 3728 3105 2663 2330 2071 1864 1553 1165 3 (12) U2403B start no Battery inserted Turn on VS > 3.5 V V3 = 1.5 V LED2 “ON” Timer start Test Open GND V S mode Divider 226 217 28 Tj > Tmax yes no V1 < 3.0 V yes V3 no [0 V Interrupt charging LED2 “OFF” Interrupt no Tj < Tmax yes no V1 > VS yes V3 = 0 V Continuous charging LED2 “ON” Continuous timing no End of timing yes LED2 “OFF” LED1 “ON” Trickle charge mode V3 = 100 mV Battery removed no yes Undervoltage reset 95 9624 Figure 3. Flow chart 4 (12) TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96 U2403B Absolute Maximum Ratings Reference point Pin 7 (GND), unless otherwise specified. Parameters Supply current t ≤ 100 ms Currents Voltages Pin 6 Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 Pin 8 Pins 1, 3, 5, 6 and 8 Pin 2 Pin 4 Junction temperature Ambient temperature Storage temperature range Symbol IS is I1 – I2 I3 I4 I5 I8 V V2 V4 Tj Tamb Tstg Value 20 100 300 310 1 15 – 75 to + 120 8 13.5 1.6 1.5 150 10 to 85 – 50 to + 150 Unit mA mA mA mA mA mA mA mA V Symbol RthJA Value Unit 120 220 140 80 K/W °C °C °C Thermal Resistance Parameters Junction ambient DIP8 SO8 on PC-board SO8 on ceramic SO8 on ceramic with thermal compound TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 5 (12) U2403B Electrical Characteristics VS = 6 V, Tamb = 25_C, reference point Pin 7 (GND), unless otherwise specified. Parameters Supply voltage limitation Test Conditions / Pins Pin 6 IS = 4 mA IS = 20 mA VS = 6 V Pin 6 Supply current Voltage monitoring Turn-on threshold Turn-off threshold Charge-mode indicator (LED) LED current LED saturation voltage I8 = 3.7 mA Leakage current Collector terminal, Figure 5 Open collector current Saturation threshold VS = 6 V Min. Typ. Max. Unit 13.5 13.7 2.2 V IS 12.5 12.6 1.4 VTON VTOFF 2.8 2.5 3.5 3.2 V I8 V8 Ilkg 3.0 – 0.35 6.0 960 1.1 mA mV mA ICO VTON VTOFF I2 15 2.55 VS–1V 250 mA 3.0 VS 55 3.35 VS–0.4V 285 I3 V3 –0.6 1.42 40 – 0.4 1.5 70 Ilkg VT(u) fosc – 0.5 875 2700 305 0.1 985 3050 345 I5 40 – 75 1.7 0.5 120 – 20 2.5 1.0 mA Pin 8 Pin 1 Shunt emitter current R3 = 5.6 W Pin 2 Operational sense amplifier, Figure 1 Pin 3 Input current V3 = 0 V Input voltage VRef = 1.5 V VRef = 100 mV VRef = 0 V Oscillator Pin 4 Leakage current V4 = 0 to 0.85 V Threshold voltage Upper Oscillator frequency R4 = 160 kW, C4 = 2.2 nF R4 = 680 kW, C4 = 4.7 nF Test mode switch (STM) Pin 5 Input current V5 = 6 V V5 = 0 V Output voltage High Low 6 (12) Symbol VS V0(H) V0(L) 0.08 1.58 100 40 V mA mA V mV mV mA mV Hz mA V TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96 U2403B Internal Temperature Switch Automatic Control Protection 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, Ich, reduces according to the equation: To reduce the design costs, it is possible to select the transformer which requires minimum power supply. Ich = V3 / R3 where Ich = 1 to 2 mA (IC supply current) The oscillator is connected to GND via Pin 3 (V3) which holds the present time status. When the chip temperature decreases below the transition value, all functions are released and the charge time is continued. The process is reversible. If there is a higher power dissipation in the circuit (Tj > 140°C), the temperature monitoring remains permanently activated (ON). The total cycle time is prolonged according to the interrupt-time duration, see figure 4. The output stage of the control is selected so that it is switched off before saturation is achieved (VCEsat = 3.0 V). 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 now an open circuit impedance. The system becomes active again if V1 ≥ VS. The advantage of the system is that if sags of short duration appear on the mains voltage or if the transformers used are too small, the charge duration is increased, but the charge capacity remains the same (see figure 5). 95 9640 Tj 140°C Tj 130°C Charge current I1 Timing Charge mode Counting timer t Figure 4. Charge duration – overtemperature 95 9633 VS –V1 3.0 V 0V Charge current I1 Timing Charge mode Counting timer t Figure 5. Charge duration – V1 TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 7 (12) U2403B Basic Equations Standard Applications Basic Example NiCd battery 750 mAh R1 = 510 W, 1/8 W Charging time: 3 h C1 = 47 F/ 16 V g current: Charge 240 mA, A 1/3 C R3 = 6.2 , 1/2 W Trickle charge: 19 mA < 1/40 C R1 = 0.5 V / IS IS = 1.8 mA R5 = V5/ (Ich – 20 mA) Nominal Charge Current: Ich = V3/R3 where V3 = 1.48 V (typ.) R4 = 300 k Trickle Current: Ich = V3/R3 + I8 + IS Typical values are: V3 = 100 mV, I8 = 4.5 mA C4 = 470 pF R5 = 8.2 , 1/2 W Minimum Supply Voltage No of Cells 1 DC Supply Minimum 6.8 V 2 8.3 V 3 9.8 V 4 11.3 V 5 12.8 V DC supply R1 READY Ich C1 IS LED1 8 6 7 5 Charge R5 U2403B Special Requirements of Different Charge Times 95 9639 LED2 1 2 3 4 R4, C4 values for different charging times R4 R4 C4 2h 4h 6h 7h 12 h 300 k 430 k 470 k 470 k 390 k 330 pF 470 pF 680 pF 1 nF 2.2 nF Special Requirements for Different Charge Current R3 C4 Figure 6. Standard application R3, R5 values for different charge current R3 R5 8 (12) 240 mA 150 mA 100 mA 50 mA 8.2 15 22 68 TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96 U2403B Booster and Trickle Charge Reduction Basic Equations Basic Example R1 = 0.5 V / IS R5 = V(LED2)/ (Ich – 20 mA) NiCd battery 1000 mAh R1 = 510 W, 1/8 W Charging time: 2 h C1 = 100 F/ 16 V Charge current: 500 mA R3 = 3 / 1 W Trickle charge: 22 mA < 1/22 C R4 = 300 k Nominal Charge Current: Ich = V3/ R3 V3 = 1.48 V, typically Trickle Current: Ich = V3/R3 + ILED1 + IS – I6 Typical values: V3 = 100 mV ILED1 = 4.5 mA IS = 1.8 mA C4 = 330 pF R5 = 3.9 / 1 W C2 = 1 F Trickle-Charge Reduction (I6) VD1 = 0.75 V I6 = (VBatt + VD1)/R6 Supply Voltage No of Cells 1 DC Supply Minimum VS = 6.5 V 2 8.0 V 3 9.5 V 4 11.0 V 5 12.5 V BYW52 DC supply D1 I6 R6 R4, C4 values for different charge times 2h 4h 6h 7h 12 h 300 k 430 k 470 k 470 k 390 k 330 pF 470 pF 680 pF 1 nF 2.2 nF R3, R5 values for different charge currents 493 mA 411 mA 296 mA 3 3.9 4.7 6.8 TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 6 7 5 U2403B R2 BD 136 or BC 636 1 2 3 4 R4 R5 Charge LED2 R3 C4 S1: use for test only Figure 7. Application for charge current > 250 mA 616 mA R6 = 560 , reduced trickle charge C2 S1 10 k Special Requirements for Different Charge Current R3 R5 8 IS 95 9623 Special Requirements for Different Charge Times R4 C4 READY LED1 Ich C1 R1 To fulfill requirements of higher charge current an external booster transistor can be used (see figure 7). As the temperature cannot be monitored in this case a heat sink with a resonable size should be used for safe operation. Test mode switch S1 can be used for accelerated production check. 9 (12) U2403B Charge System at Higher Voltage of 30 V Charge systems with higher voltages than VSmax can be realized with the additional expander circuitry, as shown in figure 8. This circuit contains a simple temperature monitoring function. When the temperature level is + + reached, the transistor, T3, is switched on. If T3 is switched on and there is current flow into Pin 5, normal charge is terminated. Battery 96 11707 R 11 DC-Supply 30 V R 10 NTC T3 BC212 – – D1 R1 green TLHG5400 R2 Ich R8 LED2 D2 8 BC212 mounted T1 on T heatsink 2 6 7 5 U2403B BD135 LED1 red TLHR5400 C2 R5 R7 R6 1 2 3 LED1 normal charge LED2 trickle charge 4 R4 R3 R1 = 1 kW, R2 = 10 kW, R3 = f(IC), R4 = f(time), R5 =10 kW/0.5 W, R6= 1 kW, R7 = 10 kW, R8 = 47 kW, R10 =10 kW, R11 = f(temp.), D1 = 1N4148, D2 = BZX85C10, C1 = 100 mF/6 V, C2 = 10 nF, C4 = 330 pF R11 = f(temp.) depends on number of cells C4 Figure 8. U2403B for higher supply voltage up to 30 V with integrated temperature monitoring No of Cells 2 3 4 5 10 (12) R11 13 kW 8.2 kW 6.2 kW 4.7 kW NTC Value 25°C 40°C 50°C 6.8 kW 3.9 kW 2.8 kW TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96 U2403B Package Information Package DIP8 Dimensions in mm 7.77 7.47 9.8 9.5 1.64 1.44 4.8 max 6.4 max 0.5 min 0.58 0.48 3.3 0.36 max 9.8 8.2 2.54 7.62 8 5 technical drawings according to DIN specifications 13021 1 4 Package SO8 Dimensions in mm 5.2 4.8 5.00 4.85 3.7 1.4 0.25 0.10 0.4 1.27 6.15 5.85 3.81 8 0.2 3.8 5 technical drawings according to DIN specifications 13034 8 TELEFUNKEN Semiconductors Rev. A2, 14–Nov–96 5 11 (12) U2403B 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 known 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. Various 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 not manufactured with ozone depleting substances and do not contain such substances. We reserve the right to make changes to improve technical design and may do so without further notice. 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-74025 Heilbronn, Germany Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423 12 (12) TELEFUNKEN Semiconductors Rev. A1, 20-Mar-96