NJU7286 New Japan Radio Co.,Ltd, NJU7286 Datasheet

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... GENERAL DESCRIPTION NJU7286 is a C-MOS IC for battery backup system. It has two regulators, two voltage detectors, a battery switching system and their control circuits. It switches regulator output to backup battery when voltage detector detects drop of main power supply. And it also outputs detection signal of main power supply and battery. ...

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... Output Voltage (V) Device Name V RO NJU7286A 3.200 NJU7286B 3.150 NJU7286C 3.300 NJU7286D 3.200 Caution: The package lineup of NJU7286D is only TVSP-8. CS voltage should be set up so that switch voltage ( Note: The selection range is as follows 2.3 to 5.4V (0.1V Step) RO, OUT -V :2.4 to 5.4V (0.1V Step) DET1 -V :1.7 to 3.4V (0.1V Step) ...

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... ELECTRICAL CHARACTERISTICS NJU7286A (C =0.1µ PARAMETER SYMBOL Total Quiescent Current Backup Power Supply Input Voltage Voltage Regulator 1 Output Voltage 1 Dropout Voltage 1 Load Regulation 1A V Load Regulation 1B V Line Regulation 1 Average Temperature Coefficient of Output Voltage 1 Voltage Regulator 2 Output Voltage 2 Dropout Voltage 2 Load Regulation 2A ...

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Switch Control Switch Voltage CS Output Inhibit Voltage V Switch Leak Current BAT V Switch Resistance BAT Average Temperature Coefficient of Switch V Voltage Average Temperature Coefficient of CS Output V Inhibit Voltage - =2.8V, BAT V ...

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... NJU7286B (C =0.1µ PARAMETER SYMBOL Total Quiescent Current Backup Power Supply Input Voltage Voltage Regulator 1 Output Voltage 1 Dropout Voltage 1 Load Regulation 1 V Line Regulation 1 Average Temperature Coefficient of Output Voltage 1 Voltage Regulator 2 Output Voltage 2 Dropout Voltage 2 Load Regulation 2 V Line Regulation 2 Average Temperature ...

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Switch Control Switch Voltage CS Output Inhibit Voltage V Switch Leak Current BAT V Switch Resistance BAT Average Temperature Coefficient of Switch V Voltage Average Temperature Coefficient of CS Output V Inhibit Voltage - =2.8V, BAT V ...

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... NJU7286C (C =0.1µ PARAMETER SYMBOL Total Quiescent Current Backup Power Supply Input Voltage Voltage Regulator 1 Output Voltage 1 Dropout Voltage 1 Load Regulation 1 V Line Regulation 1 Average Temperature Coefficient of Output Voltage 1 Voltage Regulator 2 Output Voltage 2 Dropout Voltage 2 Load Regulation 2 V Line Regulation 2 Average Temperature ...

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Switch Control Switch Voltage CS Output Inhibit Voltage V Switch Leak Current BAT V Switch Resistance BAT Average Temperature Coefficient of Switch V Voltage Average Temperature Coefficient of CS Output V Inhibit Voltage - =2.8V, BAT V ...

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... NJU7286D (C =0.1µ PARAMETER SYMBOL Total Quiescent Current Backup Power Supply Input Voltage Voltage Regulator 1 Output Voltage 1 Dropout Voltage 1 Load Regulation 1A V Load Regulation 1B V Line Regulation 1 Average Temperature Coefficient of Output Voltage 1 Voltage Regulator 2 Output Voltage 2 Dropout Voltage 2 Load Regulation 2A V OUTA ...

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... should be set 10 µA RO OUT IC or the capacitor which are connected to NJU7286 should not exceed rating by the exaggerated shot of a regulator etc. The V terminal, the V terminal and the V IN OUT The capacitor connected to the V prevent carrying out voltage descending at the time of a REG2 operation change ...

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BLOCK DIAGRAM Voltage Detector V SS Ver.2007-07-04 Short Circuit Protection Short Circuit Protection REG2 V SW1 Voltage Detector RESET Voltage Detector V SW2 Voltage Detector Switch Control V REG1 V ______________ RESET CS Short Circuit Protection V ...

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FUNCTIONAL EXPLANATION OF BLOCK 1. Voltage regulator(REG1,REG2) ▪ Output Voltage serialization is possible with 0.1V step Voltage Detector ▪ V (main power supply) terminal voltage is supervised, and the fall of the main power supply is detected. IN ...

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Timing Chart ( ( (V) 2 OUT (V) BAT ...

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... V V NJU7286 OUT BAT OUT __________ RESET - NJU7286 F BAT OUT Oscilloscope ___________ RESET 100kΩ Oscilloscope NJU7286 ...

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CORRESPOND TABLE OF TEST CIRCUIT TEST PARAMETER Quiescent Current Power Supply Voltage Operation Range Output Voltage 1 Dropout Voltage 1 Load Regulation 1 Line Regulation 1 Average Temperature Coefficient of Output Voltage 1 Output Voltage 2 Dropout Voltage 2 Load ...

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... OUT NJU7286 ______________ RESET V BAT µ 100k Ω ______________ V RESET RO CS NJU7286 V OUT V BAT V SS 0.1 F µ The backup battery can be flating-recharged by using voltage regulator 1. V REG 10 F µ 100kΩ V OUT + - 10 F µ ______________ RESET 100k Ω ...

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Ver.2007-07-04 [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not ...