ltc4095 Linear Technology Corporation, ltc4095 Datasheet
ltc4095
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ltc4095 Summary of contents
Page 1
... A thermal feedback loop regulates the charge current to limit the die temperature during high power operation or high ambient thermal conditions. The LTC4095 is available in a tiny, low profi le (0.75mm) 8-lead 2mm × 2mm DFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ...
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... PACKAGE/ORDER INFORMATION EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER LTC4095EDC Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC4095 is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LTC4095 TYPICAL PERFORMANCE CHARACTERISTICS Battery Regulation (Float) Voltage vs Battery Charge Current 4. 0.845k 4.24 PROG HPWR = 5V 4.23 4.22 4.21 4.20 4.19 4.18 4.17 4.16 4.15 0 200 400 600 800 1000 I (mA) BAT 4095 G01 Charge Current vs Battery Voltage 600 1.74k PROG 500 HPWR = 5V 400 300 200 HPWR = 0V 100 ...
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... TEMPERATURE (°C) Timer Period Accuracy vs Temperature –1 –2 85 –55 –35 – TEMPERATURE (°C) LTC4095 T = 25°C, unless otherwise noted. A SUSP/HPWR Pins Rising Threshold Voltage vs Temperature 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 85 –35 – –55 5 TEMPERATURE (°C) 4095 G10 ⎯ C ⎯ H ⎯ R ⎯ G Pin I-V Curve ...
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... C ⎯ H ⎯ R ⎯ G requires a pull-up resistor and/or LED to provide indication. SUSP (Pin 4): Suspend Mode Input. A voltage greater than 1.2V on the SUSP pin puts the LTC4095 into suspend mode, disables the charger and resets the termination timer. A weak pull-down current is internally applied to this pin to ensure it is low when the input is not being driven externally ...
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... In addition, a differential undervoltage lockout circuit disables the battery charger when IN falls to within V BAT voltage. Suspend Mode The LTC4095 can also be disabled by pulling the SUSP pin above 1.2V. In suspend mode, the battery drain cur- rent is reduced to 1.3µA and the input current is reduced to 8.5µA. LTC4095 ...
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... When the bat- tery voltage approaches the 4.2V required to maintain a full charge, otherwise known as the fl oat voltage, the charge current begins to decrease as the LTC4095 switches into constant-voltage mode. Trickle Charge and Defective Battery Detection Any time the battery voltage is below V goes into trickle charge mode and reduces the charge current to 10% of the full-scale current ...
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... LTC4095 or external components. The benefi the LTC4095 thermal regula- tion loop is that charge current can be set according to actual conditions rather than worst-case conditions with the assurance that the battery charger will automatically reduce the current in worst-case conditions ...
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... NTC As the temperature drops, the resistance of the NTC therm- istor rises. The LTC4095 is also designed to pause charging when the value of the NTC thermistor increases to 3.25 times the value of R25. For a Vishay “Curve 1” thermistor, this resistance, 325k, corresponds to approximately 0°C. The hot and cold comparators each have approximately 3° ...
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... APPLICATIONS INFORMATION Alternate NTC Thermistors and Biasing The LTC4095 provides temperature qualifi ed charging if a grounded thermistor and a bias resistor are connected to the NTC pin. By using a bias resistor whose value is equal to the room temperature resistance of the thermistor (R25) the upper and lower temperatures are pre-programmed to approximately 40° ...
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... Figure 4 and results in an upper trip point of 45°C and a lower trip point of 0°C. USB and Wall Adapter Power Although the LTC4095 is designed to draw power from a USB port to charge Li-Ion batteries, a wall adapter can also be used. Figure 5 shows an example of how to combine wall adapter and USB power inputs ...
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... 115°C – 0.75W • 60°C/W = 115°C – 45° 70°C A The LTC4095 can be used above 70°C, but the charge cur- rent will be reduced from 500mA. The approximate current at a given ambient temperature can be calculated: ° 115 C T – ...
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... Board Layout Considerations In order to deliver maximum charge current under all conditions critical that the exposed metal pad on the backside of the LTC4095 package is soldered to the PC board ground. Correctly soldered to a 2500mm double-sided 1oz. copper board the LTC4095 has a ther- mal resistance of approximately 60°C/W. Failure to make ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC4095 TYP 5 8 0.40 ± 0.10 PIN 1 NOTCH R = 0.20 OR 0.25 × ...
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... Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 500mA Single-Cell Li-Ion Charger IN 460mA 100k R1 IN BAT 510Ω LTC4095 LED C IN CHRG NTC SUSPEND SUSP PROG 100 500 HPWR 1.74k GND COMMENTS TM Simple ThinSOT Charger, No Blocking Diode, No Sense Resistor Needed Low Current Version of LTC1734, 50mA ≤ ...