ICS1722N Galaxy Semi-Conductor Holdings Limited, ICS1722N Datasheet
ICS1722N
Related parts for ICS1722N
ICS1722N Summary of contents
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QuickSaver® Charge Controller for Nickel-Cadmium and Nickel-Metal Hydride Batteries General Description The ICS1722 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 ...
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ICS1722 Pin Configuration Pin Definitions Pin Number Pin Name 1 CHG 2 DCHG 3 PFN 4 MMN 5 CMN 6 SEL0 7 VSS 8 SEL1 9 MRN AUX0 12 AUX1 13 OPREF 14 VIN 15 unused 16 ...
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Controller Operation Charging Stages The charging sequence consists of four stages. The application of current is shown graphically in Figure 1. The soft start stage gradually increases current levels up to the user selected fast charge rate during the first ...
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ICS1722 Initial Pulse Width cycle time Figure 3: Cycle-to-cycle increase of the soft-start current pulse widths Fast Charge In the second stage, the ICS1722 applies the charging current in a series of charge and discharge pulses. The technique consists of ...
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The discharge current pulse amplitude is typically set to about 2.5 times the amplitude of the charging current based on 1.4V/cell. For example, if the charge current is 4 amps, then the discharge current is set at about 10 amps. ...
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ICS1722 Charge Termination Methods Charge termination schemes include voltage slope, fast charge timer and, if desired, a ten hour timer to limit total charge time. Voltage Slope Termination The most distinctive point on the voltage curve of a charging battery ...
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Battery Detection Upon power-up or after a master reset, excess charge from output filter capacitors at the charging system terminals is removed with a series of discharge pulses. After the discharge pulse sequence is complete, the voltage at VIN must ...
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ICS1722 Direct Maintenance Mode The ICS1722 can enter directly into the C/40 maintenance mode for cells that require a maintenance charge only. The direct maintenance mode is activated by setting the AUX0 pin low (L) and the AUX1 pin high ...
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Pin Descriptions The ICS1722 requires some external components to control the clock rate and provide an indicator display. The controller must be interfaced to an external power source that will provide the current required to charge a battery pack and, ...
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ICS1722 SEL0 SEL1 Charge Rate 4C (15 min (30 min 1.3C (45 min (60 min C/1.5 (90 min C/2 (120 min C/2.5 (150 min ...
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Master Reset: MRN Pin The MRN pin is provided to re-program the controller for a new mode or charging sequence. This pin has an internal pull-up of about 75k . A logic low on the MRN pin must be present ...
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ICS1722 + 2.2k OPREF = 1.86V R4 = 1.3k Resistor divider at the OPREF pin Figure 8: Open Circuit Reference Example Power: VDD Pin The power supply for the device must be connected to the VDD ...
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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 ...
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ICS1722 R 16k , C 100pF PARAMETER Clock Frequency Reset Pulse Duration Charge Pulse Width Discharge Pulse Width Rest Time Data Acquisition Time Cycle Time Capacitor Discharge Pulse Width Capacitor Discharge Pulse Period Polling Detect Pulse Width Polling Detect Pulse ...
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Applications Information To ensure proper operation of the ICS1722, external components must be properly selected. The external current source used must meet several important criteria to ensure optimal performance of the charging system. The charging current should be constant when ...
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ICS1722 The voltage slope termination method used by the ICS1722 requires a nearly constant current flow into the battery during fast charge. Charging the battery in equipment that draws a known constant current while the battery is charging should have ...
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V CONSTANT in CURRENT SOURCE + (note 2) 390 390 1k (note 3) FAULT MAINT CHG + 5 V Notes: 1) Value of R4 determined by discharge current and capacity of battery pack. 2) ...
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... All package dimensions are in inches. 16-Pin SOIC Package (300 mil) Ordering Information: ICS1722M, ICS1722MT, ICS1722S, ICS1722ST, ICS1722N Example: ICS 1712 ST Device type: Consists digits or numbers Prefix: ICS = Intelligent Charging Solution standard device 0.018 0.405 0.130 0.296 ...
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Galaxy Power Incorporated makes no claim about the capability of any particular battery (NiCd or NiMH) to accept a fast charge. GPI strongly recommends that the battery manufacturer be consulted before fast charging. GPI shall be held harmless for any ...
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ICS1722 NOTES 20 ...
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NOTES 21 ICS1722 ...
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ICS1722 NOTES 22 ...
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NOTES 23 ICS1722 ...
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ICS1722 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 20, 1999 24 ...