LTC4012IUF-1#TRPBF Linear Technology, LTC4012IUF-1#TRPBF Datasheet

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... Portable Instruments n Battery Backup Systems n L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and PowerPath and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5723970. typical application ...

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... LTC4012CUF-2#PBF LTC4012CUF-2#TRPBF LTC4012IUF#PBF LTC4012IUF#TRPBF LTC4012IUF-1#PBF LTC4012IUF-1#TRPBF LTC4012IUF-2#PBF LTC4012IUF-2#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www ...

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T SYMBOL PARAMETER Charge Voltage Regulation V V Accuracy (See Test Circuits) TOL BAT I V Input Bias Current VFB FB R FBDIV On Resistance ON I FBDIV Output Leakage Current LEAK-FBDIV ...

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LTC4012/ LTC4012-1/LTC4012-2 electrical characteristics temperature range, otherwise specifications are at T SYMBOL PARAMETER R SHDN Pull-Down Resistance IN I CLP Shutdown Current CLPS I BAT Leakage Current LEAK-BAT I CSN Leakage Current LEAK-CSN I CSP Leakage Current LEAK-CSP I SW ...

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Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC4012C is ...

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LTC4012/ LTC4012-1/LTC4012-2 typical perForMance characteristics (T = 25°C unless otherwise noted IHLP-2525 6.8µH) A Efficiency at DCIN = 20V, BAT = 8V 100 R = 33m SENSE R = 3.01k IN 95 EFFICIENCY 90 POWER LOSS 85 80 ...

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L = IHLP-2525 6.8µH) A Charge Current Line Regulation 0.5 BAT = 6V 0 33m SENSE R = 3.01k IN 0 CHG 0.2 0 ...

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LTC4012/ LTC4012-1/LTC4012-2 pin Functions CLN (Pin 1): Adapter Input Current Limit Negative Input. The LTC4012 senses voltage on this pin to determine if less charge current should be sourced to limit total input current. The threshold is set 100mV below ...

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Functions PROG (Pin 13): Charge Current Programming and Monitor- ing Pin. An external resistance connected between PROG and GND, along with the current sense and PWM input resistors, programs the maximum charge current. The voltage on this pin can ...

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LTC4012/ LTC4012-1/LTC4012-2 block DiagraM (LTC4012) DCIN 4 – INFET CLP 2 CLN 1 ICL 8 CHRG SHUTDOWN SHUTDOWN SHDN 6 CONTROL TO INTERNAL CIRCUITS ACP 5 BAT 11 OSCILLATOR FBDIV 10 0 INPUT ...

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DiagraM (LTC4012-1/LTC4012-2) DCIN 4 – INFET CLP 2 CLN 1 ICL 8 CHRG 7 SHUTDOWN SHUTDOWN SHDN 6 CONTROL TO INTERNAL CIRCUITS FVS1 10 Output FVS0 Voltage 9 Select BAT 11 ACP 5 OSCILLATOR INPUT CURRENT ...

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LTC4012/ LTC4012-1/LTC4012-2 operation Overview The LTC4012 is a synchronous step-down (buck) current mode PWM battery charger controller. The maximum charge current is programmed by the combination of a charge current sense resistor (R SENSE resistors (R , Figure 1), and ...

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LTC4012 CLP CLOCK 2 OSCILLATOR BAT 11 the end of soft-start will depend on which loop (current, voltage or adapter limit control of the PWM. If this current is below that required by the ITH start-up threshold, ...

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LTC4012/ LTC4012-1/LTC4012-2 operation Adapter Input Current Limit The LTC4012 can monitor and limit current from the input DC supply, which is normally an AC adapter. When the programmed adapter input current is reached, charge current is reduced to maintain the ...

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The ITH output of the error amplifier is a scaled control voltage for one input of the PWM comparator CC. ITH sets a peak inductor current threshold, sensed by R1, to maintain the desired average current through R current ...

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LTC4012/ LTC4012-1/LTC4012-2 applications inForMation Programming Charge Current The formula for charge current is:  2085 . • –   CHRG R R SENSE PROG The LTC4012 operates best with 3.01k input ...

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The value of R controls the maximum value of charge PROG current which can be programmed (Q1 continuously on). PWM of the Q1 gate voltage changes the value produce lower currents. The frequency of this ...

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LTC4012/ LTC4012-1/LTC4012-2 applications inForMation Programming LTC4012-1/LTC4012-2 Output Voltage The LTC4012-1/LTC4012-2 feature precision internal bat- tery voltage feedback resistor taps configured for common lithium-ion voltages. All that is required to program the desired voltage is proper pin programming of FVS0 and ...

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The first option is to lower the power dissipation of R the expense of accuracy without changing the input current limit value. The second is to make the input current limit value programmable. The overall accuracy of this ...

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LTC4012/ LTC4012-1/LTC4012-2 applications inForMation C/10 CHRG Indicator The value chosen for R has a strong influence PROG on charge current monitoring and the accuracy of the C/10 charge indicator output (CHRG). The LTC4012 uses the voltage on the PROG pin ...

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The output capacitor shown across the battery and ground must also absorb PWM output ripple current. The general formula for this capacitor current is:   V BAT • V • 1 –   ...

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LTC4012/ LTC4012-1/LTC4012-2 applications inForMation R should not be less than 2.37k or more than 6.04k. Val- IN ues of R greater than 3.01k may cause some reduction in IN programmed current accuracy. Use these equations and guidelines, as represented in ...

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FET Selection Two external power MOSFETs must be selected for use with the charger: an N-channel power switch (top FET) and an N-channel synchronous rectifier (bottom FET). Peak gate-to-source drive levels are internally set to about 5V. Consequently, ...

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LTC4012/ LTC4012-1/LTC4012-2 applications inForMation The LTC4012 can be soft-started with the compensation capacitor on the ITH pin. At start-up, ITH will quickly rise to about 0.25V, then ramp rate set by the com- pensation capacitor and the ...

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Place the inductor input as close as possible to the switching FETs. Minimize the surface area of the switch node. Make the trace width the minimum needed to support the programmed charge current. Use no cop- per ...

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LTC4012/ LTC4012-1/LTC4012-2 package Description 4.50 ± 0.05 3.10 ± 0.05 2.45 ± 0.05 2.00 REF 2.45 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 4.00 ± 0.10 PIN 1 TOP MARK ...

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... I-Grade Parts Added. Reflected Throughout the Data Sheet 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... THE COMBINATION OF R14 AND Q4 L1 4.7µH R11 25m + D3: CMDSH-3 12.6V D4: MBR230LSFT1 Li-Ion Q1: 2N7002 BATTERY Q2, Q3: Si7212DN OR SiA914DJ OR Si4816BDY (OMIT D4) 4012 TA03 Q4, Q5: Si7423DN L1: 1HLP-2525CZER4R7M11 *: SEE TGATE BOOST SUPPLY IN APPLICATIONS INFORMATION TM package LT 0610 • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2009 4012fa ...