LTC4425EDD#PBF Linear Technology, LTC4425EDD#PBF Datasheet
LTC4425EDD#PBF
Specifications of LTC4425EDD#PBF
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LTC4425EDD#PBF Summary of contents
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... Power Meters, SuperCap Backup Circuits n PC Card/USB Modems L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION Charging 2-Cell Series Supercapacitor from Li-Ion Source ...
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... T = 43°C/W (Note 3) 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 IN 3.260 PROG V SET FOR 3.3V OUT 3.255 0 200 400 600 800 1000 1200 I (mA) ...
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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 ...
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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 750mV 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 series 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 ...
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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 USB Li-Ion 14 USB to High Peak Power 3.3V Charging 3.3V 5V, 500mA V V OUT IN 2.2μF 1.5M V MID PFI 1.2M LTC4425 FB PFI_RET V SEL PFO μC EN PROG 4425 TA03 ...
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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: CAP-XX HS203F 12V V IN 2.2μF RUN ON OFF I LIM LT3663 28.7k GND 16 ...
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TYPICAL APPLICATIONS μ Redundant High Peak Power Battery Supplies USB OUT FB V 2.2μF 1.5M MID PFI LTC4425 1.2M PFI_RET SEL EN PROG PFO USB POWER OUT IN 1.5M 2.2μ ...
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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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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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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... PROG 8 PFO R6 500Ω 4 SEL μ GND 4425 TA09 3.3V 750k 10μF 240k 1.8V 300k 4.7μF 240k 1.2V 150k 4.7μF 240k < 1μA, 3mm × 3mm 10-Lead DFN = 3.6V 0510 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 4425f ...