ICS1702 Galaxy Power, Inc., ICS1702 Datasheet
ICS1702
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ICS1702 Summary of contents
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... QuickSaver® Charge Controller for Nickel-Cadmium and Nickel-Metal Hydride Batteries General Description The ICS1702 is a CMOS device designed for the intelligent charge control of either nickel-cadmium (NiCd) or nickel-metal hydride (NiMH) batteries. The controller uses a pulsed-current charging technique together with voltage slope and/or temperature slope termination ...
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... Pin 16 has an internal pull-up. Pin 13 has an internal pull-down. Pins 7, 10, 14, 15 float to 2.3V when unconnected CHG 2 19 DCHG PFN 3 18 MMN 4 17 CMN 5 16 ICS1702 OTN SEL0 14 VSS 8 13 AVSS 9 12 SEL1 10 11 20-Pin DIP or SOIC Type Active high TTL compatible signal used to turn on an external current source to provide current to charge OUT the battery ...
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... The CMN indicator is activated continuously during this stage har ge Topp tage 2 S tage ation ation + 2 ho urs 3 ICS1702 M ain te nan rge Tim e ( le) ...
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... The ICS1702 can be set for nine user- selectable fast charge rates from 15 minutes (4C) to four hours (C/4). Charge pulses occur approximately every second. The CMN indicator is activated continuously during this stage ...
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... The maintenance charge is intended to offset the natural self- discharge of NiCd or NiMH batteries by keeping the cells primed at peak charge. After the topping charge ends, the ICS1702 begins this charge stage by extending the duty cycle of the applied current pulses to a C/40 rate. The maintenance charge will last for as long as the battery voltage is greater than 0 ...
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... Figure 6: Voltage and slope curves showing inflection and zero slope points Cells that are not thoroughly conditioned or possess an unusual cell construction may not have a normal voltage profile. The ICS1702 uses an alternate method of charge termination based on a slight decrease in the voltage slope to stop charge to cells whose voltage profile is very shallow ...
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... Figure 8: Cell temperature and thermistor voltage slope Table 1 shows the decrease in thermistor voltage the last minute before full charge required by the ICS1702 at various charge rates. The thermistor voltage slope should exceed the listed value to ensure charge termination. Note that changes in thermistor location, cell size or large ambient temperature fluctuations can affect the slope to some degree ...
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... ICS1702 To determine the required thermistor characteristics for proper temperature slope termination, the battery temperature rise must be known or determined for the last minute prior to full charge. Maximum temperature termination is also enabled when temperature slope termination is used. Care must be taken to keep voltage levels at the THERM pin within the fast charge range (between 2 ...
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... The discharge is not limited by a timer. This allows the user to set the discharge rate. The battery is drained to 1 volt/cell as read at the VIN pin under load. The ICS1702 shuts down after the discharge sequence is finished and a master reset must be performed to reactivate the device ...
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... Cold battery charging is activated if a voltage at the THERM pin is in the cold battery voltage range, as shown in Figure 9. The ICS1702 checks for a cold battery before initiating fast charge cold battery is present before fast charge begins, the ICS1702 begins a two-hour C/10 topping charge (the pulsed duty cycle is based on the selected charge rate) ...
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... DC Characteristics. To program the SEL0 and SEL1 inputs, refer to the Charge Rate List in Table 4. The ICS1702 does not control the current flowing into the battery in any way other than turning it on and off. The required current for the selected charge rate must be provided by the user’s power source ...
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... Methods for additional information on the charge timer. Mode Selection: AUX0, AUX1 Pins The AUX0 and AUX1 inputs must be programmed by the user to inform the ICS1702 of the desired auxiliary mode. When left unconnected (open) these tri-level pins will float to about 2.3V. When a low level is required, the pin must be grounded. ...
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... C and reducing the current below the resistance of the thermistor is 18k . the resistance drops to 4.7k . The ICS1702 has an internal voltage threshold 2.4V, and an internal voltage 0.93V as shown in Figure the voltage ...
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... If the voltage across the thermistor (at the THERM pin) drops below 0.93V, the ICS1702 will shut down due to a hot battery fault condition and will not restart unless reset. If the voltage dropped across the thermistor is above 2 ...
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... THERM pin must be below 0.5V for normal operation. When the thermal switch opens (see Figure 12), the internal pull-up at the THERM pin will raise the voltage above 4.2V and the ICS1702 will shut down and will not restart unless reset. Table 7 contains the internal voltage thresholds used with a thermal switch. ...
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... The voltage at this pin is compared to the voltage at the VIN pin when the current source is turned on. If the voltage at VIN is greater than the voltage at OPREF, the ICS1702 assumes the battery has been removed and the ICS1702 enters the polling detect mode. ...
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... There are two ground pins. Both pins must be connected together at the device. This point must have a direct connection to a solid ground plane. Table 9: Absolute Maximum Ratings 6.5 -0 -55 to 150 17 ICS1702 R1 = 10k 1.60V (battery present) { VIN = 2.00V (no battery 0 ...
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... ICS1702 T =25 C. All values given are typical at specified V amb Parameter Supply Voltage Supply Current High Level Input Voltage SEL0, SEL1, AUX0, AUX1 Low Level Input Voltage SEL0, SEL1, AUX0, AUX1 Open Input Voltage SEL0, SEL1, AUX0, AUX1 Low Level Input Current, pull-up ...
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... Figure see Figure see Figure A CYCLE t see Figure B RSA t see Figure B RSA t t CHG DCHG R t CYCLE t RESET 19 ICS1702 TYP 1.0 700 1048 5.0 4.0 16.4 1077 5.0 100 100 624 200 7.0 400 1050 1160 1160 temperature voltage RSA ...
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... This precaution is also applicable to the constant current source, 1.0k particularly switch mode type. Keep the ICS1702 and the 3.0k constant current source control circuits outside the power and return loop described above. These precautions will prevent high 2 ...
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... Voltage Slope Termination The voltage slope termination method used by the ICS1702 requires a nearly constant current flow into the battery during fast charge. Equipment that draws a known constant current while the battery is charging may use the voltage slope termination method. This constant current draw must be added to the fast charge current ...
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... If the MMN and CMN indicators are alternately flashing, the likely cause is no battery with the ICS1702 programmed in the discharge-to-charge auxiliary mode. If the battery is present, check wires, connectors, battery terminals, and the battery itself for an open circuit condition ...
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... R5 (note (note 5) ICS1702 4.7µF .047µF VDD 20 unused 19 VIN 18 OPREF 17 THERM 16 AUX1 15 AUX0 14 DTSEL 16k MRN 11 100pF Figure 15: Functional Diagram 23 ICS1702 + 27k (note temperature R2 sense options .047µF 10k @ 25°C (note open @ 45°C ...
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... All package dimensions are in inches. 20-Pin SOIC Package (300 mil) 0.130 All package dimensions are in inches. 20-Pin DIP Package (300 mil) Ordering Information ICS1702N, ICS1702M, ICS1702MT Example: ICS 1702 ST Device type: Consists digits or numbers Prefix: ICS = Intelligent Charging Solution standard device 0.016 ...
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... GPI was negligent regarding the design or manufacture of the part. COPYRIGHT © 1998 Galaxy Power Incorporated IMPORTANT NOTICE 25 ICS1702 ...
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... ICS1702 NOTES 26 ...
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... NOTES 27 ICS1702 ...
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... ICS1702 GPI Sales Offices Headquarters Galaxy Power, Inc. PO Box 890 2500 Eisenhower Avenue Valley Forge, PA 19482-0890 Phone: 1-610-676-0188 FAX: 1-610-676-0189 Internet: www.galaxypower.com GPI Sales Representative January 19, 1999 28 ...