LTC4425EDD LINER [Linear Technology], LTC4425EDD Datasheet
LTC4425EDD
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LTC4425EDD Summary of contents
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FEATURES n 50mΩ Ideal Diode from Smart Charge Current Profi le Limits Inrush Current n Internal Cell Balancer (No External Resistors) n Programmable Output Voltage (LDO Mode) n Programmable Current Limit IN ...
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... JMAX JA EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC4425EDD#PBF LTC4425EDD#TRPBF LTC4425IDD#PBF LTC4425IDD#TRPBF LTC4425EMSE#PBF LTC4425EMSE#TRPBF LTC4425IMSE#PBF LTC4425IMSE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER V Operating Supply Range IN I Quiescent Current from V Q(IN Quiescent Current from V Q(OUT) OUT I Quiescent Current in Shutdown SD Ideal Diode ...
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LTC4425 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Leakage Balancer V V Output Voltage MID MID V Maximum Current Sourcing Capability MID V Maximum Current Sinking Capability MID PFO, PFI_RET, PFI Output Low Voltage ...
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TYPICAL PERFORMANCE CHARACTERISTICS LDO Regulation Voltage vs Charge Current 3.295 3.290 3.285 3.280 3.275 3.270 3.265 V = 3.8V 10mA IN OUT 3.260 PROG V SET FOR 3.3V OUT 3.255 0 200 400 600 800 ...
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LTC4425 TYPICAL PERFORMANCE CHARACTERISTICS Logic Inputs (EN and SEL) Threshold Voltage vs Temperature 0 3.8V IN 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 –45 –25 – TEMPERATURE (°C) 4425 G10 Charge Current ...
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PIN FUNCTIONS V (Pin 1, 2): Output Pin of the Charger. Typically con- OUT nects to the top of the 2-cell supercap stack. PROG (Pin 3): Charge Current Program and Charge Current Monitor Pin. A resistor connected from PROG to ...
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LTC4425 BLOCK DIAGRAM 1. BANDGAP 1.11V REFERENCE 0.1V CHARGE CURRENT PROFILE GENERATOR 10X 1X V – V 250mV 150mV IN OUT V – OUT COMPARATOR 250mV – OUT R ...
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OPERATION The LTC4425 is a linear charger designed to charge a two-cell supercap stack by employing a constant-current, constant-voltage, and constant-temperature architecture. It has two modes of operation: charge current profi le mode (also referred to as normal mode) and ...
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LTC4425 OPERATION Thermal Regulation In either mode, if the die temperature starts to approach 105°C due to internal power dissipation, a thermal regula- tor limits the die temperature to approximately 105°C by reducing the charge current. Even in thermal regulation, ...
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OPERATION Output Status Monitor The LTC4425 has an internal comparator to always monitor the output voltage any time OUT 7.5% of its fi nal programmed value in LDO mode or more than 250mV below the ...
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LTC4425 APPLICATIONS INFORMATION Programming the Output Voltage In LDO mode, the LTC4425 output voltage can be pro- grammed for any voltage between 2.7V and V a resistor divider from V pin to GND via the FB pin OUT such that: ...
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APPLICATIONS INFORMATION Charge Current Reduction by the Thermal Regulator To protect the part against excessive heat generated by internal power dissipation, the LTC4425 is equipped with a thermal regulator which automatically reduces the charge current to maintain a maximum die ...
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LTC4425 TYPICAL APPLICATIONS + 14 USB to High Peak Power 3.3V Charging USB 3.3V 5V, 500mA V V OUT IN 1.5M V MID PFI 1.2M LTC4425 FB PFI_RET 470k SEL PFO μC EN PROG 2k 4425 TA03 3 × AA ...
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TYPICAL APPLICATIONS USB V BUS D0 R1 100k D1 μ 10μF CHRG 0805 NTC CLPROG R5 R2 8.2Ω 100k C2 R3 0.1μF 2.94k 0603 L1: COILCRAFT LPS4018-332MLC M1: SILICONIX Si2333 R2: VISHAY-DALE NTHS0603N011-N1003F C1, C3: MURATA GRM21BR61A106KE19 C2: ...
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LTC4425 TYPICAL APPLICATIONS 12V V BOOST IN SW LT3505 SHDN FB RT GND V C 75k 69.8k 1μF 70pF D1: 1N4148 D2: MBRM140 CSP1, CSP2: 12V V IN 2.2μF RUN ON OFF I LIM LT3663 28.7k GND 16 12V to ...
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TYPICAL APPLICATIONS μC Redundant High Peak Power Battery Supplies USB OUT FB V 1.5M MID PFI LTC4425 1.2M PFI_RET SEL EN PROG PFO USB POWER OUT 1. MID PFI ...
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LTC4425 PACKAGE DESCRIPTION 3.50 ±0.05 2.10 ±0.05 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING IS NOT A ...
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PACKAGE DESCRIPTION 2.845 ± 0.102 (.112 ± .004) 5.23 (.206) MIN 0.42 ± 0.038 (.0165 ± .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT ...
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LTC4425 TYPICAL APPLICATION 6V to 36V V IN 2.2μF CAR BATTERY RUN ON OFF V LT3684 C 20k RT 330pF 28.7k PG GND D1: DIODES INC. DFLS240 L1: SUMIDA CDRH4D22/HP-2R2 L2: WURTH 7440430022 L3, L4 WURTH 744031002 CSP1, CSP2: RELATED ...