LTC4065 LINER [Linear Technology], LTC4065 Datasheet

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FeaTures Switching Regulator Makes Optimal Use of Limited n Power Available from USB Port to Charge Battery and Power Application 180mΩ Internal Ideal Diode Plus Optional External n Ideal Diode Controller Seamlessly Provides Low Loss Power Path When Input Power ...

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LTC4088 absoluTe MaxiMuM raTings (Note 1) V (Transient) t < 1ms, Duty Cycle < –0. BUS V (Static), BAT, CHRG, NTC, D0, BUS D1, D2 .......................................................... –0. ....................................................................3mA CLPROG ................................................................2mA ...

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T SYMBOL PARAMETER I V Current Available Before OUT OUT Discharging Battery V CLPROG Servo Voltage in Current Limit CLPROG V V Undervoltage Lockout UVLO BUS BAT Differential Undervoltage ...

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LTC4088 elecTrical characTerisTics temperature range, otherwise specifications are at T SYMBOL PARAMETER R Battery Charger Power FET ON_CHG On-Resistance (Between V OUT T Junction Temperature in Constant LIM Temperature Mode NTC V Cold Temperature Fault Threshold COLD Voltage V Hot ...

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Typical perForMance characTerisTics Ideal Diode V-I Characteristics 1.0 INTERNAL IDEAL DIODE WITH SUPPLEMENTAL EXTERNAL VISHAY 0.8 Si2333 PMOS 0.6 INTERNAL IDEAL DIODE ONLY 0.4 0 BUS BUS 0 0 0.04 0.08 0.12 0.16 FORWARD ...

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LTC4088 Typical perForMance characTerisTics Output Voltage vs Output Current in Suspend 5.0 5x MODE 4.5 4.0 3.5 1x MODE 3 BUS V = 3.3V BAT R = 2.94k CLPROG 2.5 0 0.5 1 1.5 2 OUTPUT CURRENT ...

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Typical perForMance characTerisTics CHRG Pin Current vs Voltage (Pull-Down State) 100 BUS V = 3.8V BAT CHRG PIN VOLTAGE (V) 4088 G19 pin FuncTions NTC (Pin 1): ...

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LTC4088 pin FuncTions CHRG (Pin 7): Open-Drain Charge Status Output. The CHRG pin indicates the status of the battery charger. Four possible states are represented by CHRG: charging, not charging (or float charge current less than programmed end of charge ...

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DiagraM LTC4088 4088fb 9 ...

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LTC4088 operaTion Introduction The LTC4088 includes a PowerPath controller, battery charger, internal ideal diode, optional external ideal diode controller, SUSPEND LDO and an always-on 3.3V LDO. Designed specifically for USB applications, the PowerPath controller incorporates a precision average input current ...

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V , load current will be drawn from the battery via BUS the ideal diodes even when the battery charger is enabled. The current at CLPROG is a precise fraction of the V current. When a programming resistor ...

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LTC4088 operaTion Ideal Diode from BAT to V OUT The LTC4088 has an internal ideal diode as well as a controller for an optional external ideal diode. Both the internal and the external ideal diodes are always on and will ...

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Battery Charger The LTC4088 includes a constant-current/constant-voltage battery charger with automatic recharge, automatic ter- mination by safety timer, low voltage trickle charging, bad cell detection and thermistor sensor input for out of temperature charge pausing. When a battery charge ...

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LTC4088 operaTion microprocessor. An open-drain output, the CHRG pin can drive an indicator LED through a current limiting resis- tor for human interfacing or simply a pull-up resistor for microprocessor interfacing. To make the CHRG pin easily recognized by both ...

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NTC Thermistor The battery temperature is measured by placing a negative temperature coefficient (NTC) thermistor close to the bat- tery pack. The NTC circuitry is shown in the Block Diagram. To use this feature, connect the NTC thermistor, R ...

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LTC4088 applicaTions inForMaTion CLPROG Resistor and Capacitor As described in the Step-Down Input Regulator section, the resistor on the CLPROG pin determines the average input current limit in each of the six current limit modes. The input current will be ...

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Table 3. Recommended Inductors for the LTC4088 INDUCTOR TYPE LPS4018 D53LC DB318C WE-TPC Type M1 CDRH6D12 CDRH6D38 V and V Bypass Capacitors BUS OUT The style and value of capacitors used with the LTC4088 determine several important parameters ...

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LTC4088 applicaTions inForMaTion power to charge the battery as quickly as possible, and with minimal power dissipation within the charger. Alternate NTC Thermistors and Biasing The LTC4088 provides temperature qualified charging if a grounded thermistor and a bias resistor are ...

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From the Vishay Curve 1 R-T characteristics 60°C. Using the above equation, R 46.4k. With this value the cold trip point is about NOM 16°C. Notice that the span is now 44°C rather ...

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LTC4088 applicaTions inForMaTion Voltage overshoot on V may sometimes be observed BUS when connecting the LTC4088 to a lab power supply. This overshoot is caused by long leads from the power supply Twisting the wires together from ...

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Typical applicaTions with NTC Qualified Charging and Reverse Input Protection WALL M2 USB WALL USB High Efficiency Battery Charger/USB Power Manager V BUS µC LTC4088 100k D2 C1 CHRG 10µF 0805 NTC CLPROG PROG ...

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LTC4088 package DescripTion Please refer to http://www.linear.com/designtools/packaging/ 3.60 ±0.05 2.20 ±0.05 1.70 ±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 (SEE NOTE 6) 0.200 REF NOTE: ...

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Rev B) REV DATE DESCRIPTION B 05/12 Clarified thermistor part number. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology ...

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... LTC4088 relaTeD parTs PART NUMBER DESCRIPTION Battery Chargers LTC4057 Lithium-Ion Linear Battery Charger LTC4058 Standalone 950mA Lithium-Ion Charger in DFN LTC4065/LTC4065A 750mA Linear Lithium-Ion Battery Charger LTC4411/LTC4412 Low Loss Single PowerPath Controllers in ThinSOT LTC4413 Dual Ideal Diodes Power Management LTC3406/LTC3406A 600mA (I ), 1.5MHz, Synchronous ...