LTC3526LBEDC-2#PBF Linear Technology, LTC3526LBEDC-2#PBF Datasheet

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... NOT RECOMMENDED FOR NEW DESIGNS Contact Linear Technology for Potential Replacement FeAtures Delivers 3.3V at 100mA from a Single Alkaline/ n NiMH Cell or 3.3V at 200mA from Two Cells V Start-Up Voltage: 850mV Operating Range: 0. 1.6V to 5.25V V Range n OUT Up to 94% Efficiency n Output Disconnect n 2MHz Fixed Frequency Operation ...

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LTC3526-2/LTC3526B-2 Absolute MAxiMuM rAtings (Note 1) V Voltage . .................................................. –0. Voltage DC . ........................................................... –0. Pulsed <100ns ......................................... –0. SHDN, FB Voltage ........................................ –0. ............................................................ –0. OUT Operating Temperature Range (Note 2) ...–40°C to 85°C Storage Temperature Range .................. –65°C to 150°C orDer inForMAtion LEAD FREE FINISH TAPE AND REEL LTC3526EDC-2#PBF LTC3526EDC-2#TRPBF LTC3526BEDC-2#PBF ...

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Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3526E-2 is guaranteed to meet performance specifications from 0°C to 85°C. Specifications over –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: Specification is guaranteed by design and not 100% tested in production. typicAl perForMAnce chArActeristics Efficiency vs Load Current and V IN for V = 1.8V (LTC3526-2) OUT 100 1. ...

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LTC3526-2/LTC3526B-2 typicAl perForMAnce chArActeristics Start-Up Delay Time 100 3.0 4.5 1.0 1.5 2.0 2.5 3.5 4.0 V (V) IN 35262b2 G07 Burst Mode Threshold Current vs V ...

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V vs Temperature FB 0.50 NORMALIZED TO 25°C 0.25 0 –0.25 –0.50 –0.75 –1.00 –60 –40 – TEMPERATURE (°C) 35262b2 G13 Fixed Frequency Switching Waveform and V Ripple OUT SW PIN 2V/DIV V ...

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LTC3526-2/LTC3526B-2 typicAl perForMAnce chArActeristics Load Step Response (Fixed Frequency) V OUT 100mV/DIV AC-COUPLED LOAD CURRENT 50mA/DIV V = 1.2V 100µs/DIV 3.3V OUT 50mA TO 100mA STEP C = 10µF OUT pin Functions SW (Pin 1): Switch Pin. Connect inductor between SW and V . Keep PCB trace lengths as short and wide as possible ...

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DiAgrAM V IN 0.85V 2.2µF ANTI-RING SHDN 4 SHUTDOWN 4M V REF UVLO START-UP 2MHz OSC THERMAL SHUTDOWN operAtion (Refer to Block Diagram) The LTC3526-2/LTC3526B-2 are 2MHz synchronous boost converters housed in a 6-lead 2mm × 2mm DFN package. With the ability to start up and operate from inputs less than 1V, these devices feature fixed frequency, current mode PWM control for exceptional line and load regula- ...

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LTC3526-2/LTC3526B-2 operAtion (Refer to Block Diagram) exceeds the input by 0.24V, the IC powers itself from V instead this point the internal circuitry has OUT IN no dependency on the V input voltage, eliminating the IN requirement for a large input capacitor. The input voltage can drop as low as 0.5V. The limiting factor for the ap- plication becomes the availability of the power source to supply sufficient energy to the output at low voltages, and maximum duty cycle, which is clamped at 90% typical. Note that at low input voltages, small voltage drops due to series resistance become critical, and greatly limit the power delivery capability of the converter. LOW NOISE FIXED FREQUENCY OPERATION Soft-Start The LTC3526-2/LTC3526B-2 contain internal circuitry to provide soft-start operation. The soft-start circuitry slowly ...

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Block Diagram) when this current reduces to approximately 30mA. This prevents the inductor current from reversing in polarity, improving efficiency at light loads. Synchronous Rectifier To control inrush current and to prevent the inductor current from running away when V OUT P-channel MOSFET synchronous rectifier is only enabled when V > 0.24V). OUT IN Anti-Ringing Control The anti-ringing control connects a resistor across the inductor to prevent high frequency ringing on the SW pin during discontinuous current mode operation. Although the ringing of the resonant circuit formed by L and C ...

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LTC3526-2/LTC3526B-2 ApplicAtions inForMAtion V > V OPERATION IN OUT The LTC3526-2/LTC3526B-2 will maintain voltage regula- tion even when the input voltage is above the desired output voltage. Note that the efficiency is much lower in this mode, and the maximum output current capability will be less. Refer to the Typical Performance Characteristics. SHORT-CIRCUIT PROTECTION The LTC3526-2/LTC3526B-2 output disconnect feature allows output short circuit while maintaining a maximum internally set current limit. To reduce power dissipation under short-circuit conditions, the peak switch current limit is reduced to 400mA (typical). SCHOTTKY DIODE Although it is not required, adding a Schottky diode from will improve efficiency by about 2%. Note OUT that this defeats the output disconnect and short-circuit protection features. PCB ...

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ApplicAtions inForMAtion inductor current without saturating. Molded chokes and some chip inductors usually do not have enough core area to support the peak inductor currents of 700mA seen on the LTC3526-2/LTC3526B-2. To minimize radiated noise, use a shielded inductor. See Table 1 for suggested components and suppliers. Table 1. Recommended Inductors VENDOR PART/STYLE Coilcraft LPO4815 (847) 639-6400 LPS4012, LPS4018 www.coilcraft.com MSS5131 MSS4020 MOS6020 ME3220 DS1605, DO1608 Coiltronics SD10, SD12, SD14, SD18, SD20, www.cooperet.com SD52, SD3114, SD3118 FDK MIP3226D4R7M, MIP3226D3R3M (408) 432-8331 MIPF2520D4R7 ...

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LTC3526-2/LTC3526B-2 typicAl ApplicAtions 1-Cell to 1.8V Converter with <1mm Maximum Height for Low-Noise Applications 2.2µ OUT 1V TO 1.6V 1µF LTC3526B-2 OFF ON SHDN FB GND * FDK MIPF2520D2R2 ** MURATA GRM219R60J475KE19D 2.7µH* SW ...

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ApplicAtions 3.3µ OUT 2V TO 3.2V 1µF LTC3526-2 OFF ON SHDN FB GND *TAIYO-YUDEN NP03SB3R3M 3.3µ OUT 2.7V TO 4.3V 1µF LTC3526-2 OFF ON SHDN FB GND ...

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LTC3526-2/LTC3526B-2 pAckAge Description 2.55 0.05 0.61 0.05 1.15 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF  DC Package 6-Lead Plastic DFN (2mm × 2mm) (Reference LTC DWG # 05-08-1703 Rev B) 0.70 0.05 PACKAGE ...

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... Updated Note 6 Updated Shutdown section Updated Related Parts 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC3526-2/LTC3526B-2 PAGE NUMBER ...

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... LDO DC/DC : 0.85V to 5V 5.25V 9µA, IN OUT(MAX 0.88V to 4.5V 3V 7µA, IN OUT 4.5V 3. OUT(MAX) : 1.8V to 4.5V 5V, IN OUT(MAX 5V 5V 19µA/300µA, IN OUT(MAX 0. 5.25V 12µA, IN OUT(MAX 0910 REV C • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2006 = 7µA, Q 35262b2fc ...