LT1239CS Linear Technology, LT1239CS Datasheet
LT1239CS
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LT1239CS Summary of contents
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... A comparator is included which provides automatic switchover from main 5V power to backup power ensur- ing uninterrupted power for memory and power monitor- , LTC and LT are registered trademarks of Linear Technology Corporation. Lithium-Ion Backup System 10 INPUT 2 OUT 1 ...
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... LOAD 0mA 3.75V LOAD IN1 I = 30mA 3.75V LOAD IN1 I = 50mA 3.75V LOAD IN1 INFORMATION ORDER PART TOP VIEW NUMBER 1 16 OUT MON1 LT1239CS 3 14 INPUT OUT MON2 7 10 INPUT PACKAGE 16-LEAD PLASTIC SO = 100 C, = 120 MIN TYP MAX 3.700 3.750 3.800 3.650 3 ...
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ELECTRICAL CHARACTERISTICS PARAMETER Regulator 1 (Notes 7, 8) Shutdown Threshold Shutdown Pin Current (Note 13) Quiescent Current in Shutdown (Note 10) Ripple Rejection Current Limit Reverse Output Current Current Monitor Pin Output Current Comparator Output Saturation Voltage (V – V ...
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LT1239 ELECTRICAL CHARACTERISTICS PARAMETER Offset Voltage Output Current Sourcing Sinking Regulator 2, Low Battery Detector and Error Amplifier Quiescent Current The denotes specifications which apply over the full operating temperature range. Note 1: All voltages are with respect to the ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Regulator 2 I Current vs MON2 Output Current 250 V = 6.8V IN2 IMON2 200 150 100 OUTPUT CURRENT (mA) LT1239 • TPC04 Comparator ...
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LT1239 PIN FUNCTIONS ADJ (Pin 1): Adjust Pin of Regulator 1. The regulator will servo the adjust pin to 3.75V referred to ground. Bias current will be approximately 50nA and will flow into the adjust pin. GND ...
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U U FUNCTIONAL DESCRIPTIO Comparator: The output of the comparator is connected to the output of regulator 2. This point provides power to memory and power management circuitry. The compara- tor looks at the main 5V power line and the ...
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LT1239 U U APPLICATIONS INFORMATION 3. Protection: Regulator 1 allows the use of current limit- ing resistors to prevent overcharging lithium-ion cells. A low-battery detector shuts down regulator 2 and the error amplifier to prevent over discharging the lithium cells. ...
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U U APPLICATIONS INFORMATION Using the Current Monitor Function The current monitor pin outputs a current proportional to the output current of the regulator. Both regulator 1 and regulator 2 have independent current monitor pins. The current monitor function can ...
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LT1239 U U APPLICATIONS INFORMATION system power and the backup batteries. The comparator output will be driven high if the output of the 5V system supply is greater than the 4.85V output of regulator 2. Regulator 2 will act as ...
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... Figure 5. Adding a Protection Resistor for Lithium-Ion Charger Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... TYP SO16 0893 COMMENTS Low-Battery Detector 20 A Supply Current 0.4V Dropout Voltage at 150mA Minimum External Components Charges Battery and Provides Gas Gauge 6 A Quiescent Current Charges NiCd, NiMH LT/GP 0695 10K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1995 + POWER MONITORING CIRCUITRY ...