LTC3537EUD#TRPBF Linear Technology, LTC3537EUD#TRPBF Datasheet
LTC3537EUD#TRPBF
Specifications of LTC3537EUD#TRPBF
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LTC3537EUD#TRPBF Summary of contents
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... Additional features include a low shutdown current of under 1μA and thermal overload protection. The integrated LDO regulator provides a very low noise, programmable low dropout supply. L, LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3537EUD#PBF LTC3537EUD#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER R NMOS Switch On Resistance NMOS R PMOS Switch On Resistance PMOS I NMOS Current Limit LIM t Current Limit Delay Time to LIMDELAY Output Max Duty Cycle ...
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LTC3537 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER PSRR Ripple Rejection I Short Circuit Current Limit SHORT V ENLDO Input High Voltage ENLDOH V ENLDO Input Low Voltage ENLDOL I ENLDO Input Current ENLDO V ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current and V for V = 1.8V INB OUTB 100 INB V = 1.2V INB 1.5V INB 20 PLOSS AT V ...
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LTC3537 TYPICAL PERFORMANCE CHARACTERISTICS Burst Mode Threshold Current vs V INB 3.3V OUTB C = 10μF OUT L = 2.2μ LEAVE BURST 30 ENTER BURST 0.8 1.2 1.4 1.6 1.8 2 2.2 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Fixed Frequency Switching Waveform and V Ripple OUTB SW 2V/DIV V OUTB 20mV/ DIV 3537 G19 200ns/DIV V = 2.4V INB V = 3.3V OUTB C = 4.7μF OUTB Load Current Step Response (from Burst Mode Operation) ...
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LTC3537 TYPICAL PERFORMANCE CHARACTERISTICS LDO Current Limit vs Temperature 7 NORMALIZED TO 25° –1 –2 –40 – TEMPERATURE (°C) LDO Load Current Step Response V OLDO 100mV/ DIV I LOAD 100mA/ ...
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PIN FUNCTIONS MODE (Pin 1): Logic Controlled Input for the Auto-Burst Mode Feature. MODE = High: PWM operation with Burst Mode Operation MODE = Low: PWM operation only LBI (Pin 2): Low-Battery Comparator Non-Inverting Input. (Comparator enabled with ENBST or ...
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LTC3537 BLOCK DIAGRAM V OUT V BEST V BEST SHUTDOWN SHUTDOWN ENBST ENLDO V V REF REF UVLO STARTUP 2.2MHz OSC THERMAL SHUTDOWN + 1.13V PGDB – FBB + 0.55V PGDL – FBL GATE DRIVERS ...
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OPERATION The LTC3537 is a 2.2MHz synchronous step-up (boost) converter and LDO regulator housed in a 16-lead 3mm × 3mm QFN package. Included with the ability to start up and operate from inputs less than 0.7V, the LTC3537 features fi ...
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LTC3537 OPERATION Boost Current Limit The current limit comparator shuts off the N-channel MOSFET switch once its threshold is reached. The cur- rent limit comparator delay to output is typically 40ns. Peak switch current is limited to approximately 750mA, independent ...
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OPERATION Burst Mode operation is inhibited during start-up and soft- start and until least 0.24V greater than V OUTB The LTC3537 will operate at a continuous PWM frequency of 2.2MHz by connecting MODE to GND. At very ...
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LTC3537 APPLICATIONS INFORMATION V > V OPERATION INB OUTB The LTC3537 step-up converter will maintain voltage regu- lation even when the input voltage is above the desired output voltage. Note that the effi ciency is much lower in this mode, ...
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APPLICATIONS INFORMATION 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, www.cooperet.com SD20, SD52, SD3114, SD3118 FDK MIP3226D4R7M, (408) 432-8331 MIP3226D3R3M www.fdk.com MIPF2520D4R7 MIPWT3226D3R0 Murata ...
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LTC3537 APPLICATIONS INFORMATION For the step-up converter, a tantalum capacitor may be used in demanding applications that have large load transients. Another method of improving the transient response is to add a small feedforward capacitor across the top resistor of ...
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TYPICAL APPLICATIONS + ALKALINE 0.8V TO 1.6V 1μF + 2-CELL ALKALINE 1.6V TO 3.2V 2-CELL + ALKALINE 1.6V TO 3.2V 1μF 1-Cell to 3.3V, 2.8V 2.2μ 665k INB OUTB LTC3537 LBI V INL LBO R5 1M ...
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LTC3537 TYPICAL APPLICATIONS + Li-Ion 2.8V TO 4.2V 1μF USB OR 0.8V TO 1.6V 5V ADAPTER ALKALINE + 1μF OFF ON PWM BURST 18 Li-Ion to 5V, 3.3V 2.2μ INB OUTB LTC3537 LBI V INL ...
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... ON THE TOP AND BOTTOM OF PACKAGE 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. UD Package 16-Lead Plastic QFN (3mm × ...
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... Converter with Output Disconnect LTC3526/ 600mA Micropower Synchronous Step-Up DC/DC LTC3526L Converter with Output Disconnect LTC3528/ 1A, 1MHz, Synchronous Step-Up DC/DC Converters LTC3528B ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● COMMENTS 97% Effi ...