LTC4088-2 Linear Technology, LTC4088-2 Datasheet
LTC4088-2
Related parts for LTC4088-2
LTC4088-2 Summary of contents
Page 1
... An ideal diode ensures that system power is available from the battery when the input current limit is reached or if the USB or wall supply is removed. The LTC4088-1/LTC4088-2 is available in the low profi le 14-Lead 4mm × 3mm × 0.75mm DFN surface mount package. U 3.3µ ...
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... LTC4088-1/LTC4088-2 www.DataSheet4U.com ABSOLUTE AXI U RATI GS (Note 1) V (Transient) t < 1ms, Duty Cycle < –0. BUS (Static), BAT, CHRG, NTC, D0, V BUS D1, D2 .......................................................... –0. ....................................................................3mA CLPROG ................................................................2mA PROG C/X I ......................................................................75mA CHRG I .............................................................................2A OUT I .............................................................................. .............................................................................2A BAT Maximum Operating Junction Temperature .......... 125°C Operating Temperature Range.................. – ...
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... C/X Threshold Voltage C/X h Battery Charge Current Ratio to C/X C/X CHRG Pin Output Low Voltage V CHRG CHRG Pin Input Current I CHRG LTC4088-1/LTC4088-2 l The denotes the specifi cations which apply over the full operating = 25° 5V, BAT = 3.8V BUS CLPROG CONDITIONS 1x Mode, BAT = 3.3V 5x Mode, BAT = 3.3V 10x Mode, BAT = 3 ...
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... LTC4088-1/LTC4088-2 www.DataSheet4U.com ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER R Battery Charger Power FET ON_CHG On-Resistance (Between V T Junction Temperature in Constant LIM Temperature Mode NTC V Cold Temperature Fault Threshold COLD Voltage V Hot Temperature Fault Threshold HOT ...
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... BUS 2.94k CLPROG PROG I = 0mA OUT 88 5x CHARGING EFFICIENCY 86 1x CHARGING 84 EFFICIENCY 2.7 3.0 3.3 3.6 BATTERY VOLTAGE (V) LTC4088-1/LTC4088 25°C unless otherwise noted. A Output Voltage vs Output Current (Battery Charger Disabled) 4. BAT 4.25 4. 3.4V BAT 3.75 3.50 3.25 0 200 400 600 3.9 4.2 OUTPUT CURRENT (mA) 408812 G02 ...
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... LTC4088-1/LTC4088-2 www.DataSheet4U.com W TYPICAL PERFOR A CE 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 (mA) Battery Charge Current vs Temperature 600 PROG 500 400 THERMAL REGULATION 300 200 100 0 –40 – 100 ...
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... D2 (Pin 4): Mode Select Input Pin. D2, in combination with the D0 pin and D1 pin, controls the current limit and battery charger functions of the LTC4088-1/LTC4088-2. The LTC4088-1 and LTC4088-2 differ only in the functionality of the D2 pin default ( state (see Table 1). This pin is pulled low by a weak current sink. ...
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... D0 (Pin 13): Mode Select Input Pin. D0, in combina- tion with the D1 pin and the D2 pin, controls the current limit and battery charger functions of the LTC4088-1/ LTC4088-2 (see Table 1). This pin is pulled low by a weak current sink. D1 (Pin 14): Mode Select Input Pin. D1, in combination ...
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... W BLOCK DIAGRA LTC4088-1/LTC4088-2 40881fb 9 ...
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... USB power. Because power is conserved, the LTC4088-1/ LTC4088-2 allows the load current on V current drawn by the USB port without exceeding the USB load specifi cations. The switching regulator and battery charger communicate to ensure that the average input current never exceeds the USB specifi ...
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... I • h VBUS BUSQ R CLPROG where I is the quiescent current of the LTC4088- BUSQ 1/LTC4088- the CLPROG servo voltage in CLPROG current limit the value of the programming CLPROG resistor and h is the ratio of the measured current CLPROG the sample current delivered to CLPROG. Refer ...
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... U OPERATIO Ideal Diode from BAT to V OUT The LTC4088-1/LTC4088-2 has an internal ideal diode as well as a controller for an external ideal diode. Both the internal and the external ideal diodes are always on and will respond quickly whenever V If the load current increases beyond the power allowed from the switching regulator, additional power will be pulled from the battery via the ideal diodes ...
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... An open-drain output, the CHRG pin can , it RECHRG drive an indicator LED through a current limiting resistor for human interfacing or simply a pull-up resistor for microprocessor interfacing. UVLO BUS LTC4088-1/LTC4088-2 is removed and then BUS 1031 V 1031 ...
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... LED while a microprocessor would be able to decode either the 12.5% or 87.5% duty cycles as a bad cell fault. Because the LTC4088-1/LTC4088 3-terminal Power- Path product, system load is always prioritized over battery charging. Due to excessive system load, there may not be suffi ...
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... As the temperature drops, the resistance of the NTC thermistor rises. The LTC4088-1/ LTC4088-2 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° ...
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... If the input current is less than 100mA, the measurement accuracy may be reduced, but it does not affect the average current loop since it will not be in regulation. The LTC4088-1/LTC4088-2 includes a current-reversal comparator which monitors inductor current and dis ables the synchronous rectifi ...
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... U U APPLICATIO S I FOR ATIO Table 3. Recommended Inductors for the LTC4088-1/LTC4088-2 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 LTC4088-1/LTC4088-2 determine several important parameters such as regulator control-loop stability and input voltage ripple ...
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... NOM Optional temperature range adjustment resistor (see Figure 4b) The trip points for the LTC4088-1/LTC4088-2’s tempera- ture qualifi cation are internally programmed at 0.349 • V for the hot threshold and 0.765 • V BUS threshold. Therefore, the hot trip point is set when: ...
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... USB Inrush Limiting The USB specifi cation allows at most 10µF of downstream capacitance to be hot-plugged into a USB hub. In most LTC4088-1/LTC4088-2 applications, 10µF should be enough to provide adequate fi ltering on V capacitance is required, the following circuit can be used to soft-connect additional capacitance. ...
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... Board Layout Considerations The Exposed Pad on the backside of the LTC4088-1/ LTC4088-2 package must be securely soldered to the PC board ground. This is the only ground pin in the package, and it serves as the return path for both the control circuitry and the synchronous rectifi er. ...
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... U U APPLICATIO S I FOR ATIO Battery Charger Stability Considerations The LTC4088-1/LTC4088-2’s battery charger contains both a constant-voltage and a constant-current control loop. The constant-voltage loop is stable without any compensation when a battery is connected with low impedance leads. Excessive lead length, however, may add enough series inductance to require a bypass capacitor of at least 1µ ...
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... TYPICAL APPLICATIO S WALL M2 USB 22 U High Effi ciency Battery Charger/USB Power Manager with NTC Qualifi ed Charging and Reverse Input Protection V BUS LTC4088-1/ µC 100k D2 LTC4088-2 C1 CHRG 10µF 0805 NTC CLPROG PROG 100k 0.1µF 8.2Ω 2.94k 0603 C1, C3: MURATA GRM21BR61A106KE19 ...
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... Plastic DFN (4mm × 3mm) (Reference LTC DWG # 05-08-1708 Rev B) 0.70 ±0.05 3.30 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 3.00 REF 4.00 ±0.10 (2 SIDES 0.05 TYP 3.00 ±0.10 (2 SIDES) 0.75 ±0.05 0.00 – 0.05 LTC4088-1/LTC4088 0.115 0.40 ± 0.10 TYP 8 14 3.30 ±0.10 1.70 ± 0.10 PIN 1 NOTCH R = 0.20 OR 0.35 × 45° CHAMFER (DE14) DFN 0806 REV 0.25 ± 0.05 0.50 BSC 3.00 REF BOTTOM VIEW— ...
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... LTC4088-1/LTC4088-2 www.DataSheet4U.com 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 ( ...