LTC3440EMS#TR Linear Technology, LTC3440EMS#TR Datasheet
LTC3440EMS#TR
Specifications of LTC3440EMS#TR
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LTC3440EMS#TR Summary of contents
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... The LTC3440 is available in the 10-pin thermally enhanced MSOP and (3mm × 3mm) DFN packages. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. Protected by U.S. Patents including 6404251, 6166527. ...
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LTC3440 ABSOLUTE AXI U RATI GS (Note Voltage........................................ – 0. OUT SW1, SW2 Voltage ..................................... – 0. FB, SHDN/SS MODE/SYNC Voltage .................................. ...
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ELECTRICAL CHARACTERISTICS range, otherwise specifications are PARAMETER Error Amp AVOL Error Amp Source Current Error Amp Sink Current SHDN/SS Threshold SHDN/SS Input Current Note 1: Absolute Maximum Ratings are those values beyond which the life of the ...
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LTC3440 W U TYPICAL PERFOR A CE CHARACTERISTICS Switch Pins in Buck Mode SW1 2V/DIV SW2 2V/DIV 250ns/DIV 3440 G07 3.3V OUT I = 250mA OUT Active Quiescent Current 550 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Feedback Voltage Line Regulation 2.5V TO 5.5V IN OUT –55 – 125 TEMPERATURE (°C) 3440 G16 Boost Max Duty Cycle 90 ...
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LTC3440 CTIO S R (Pin 1): Timing Resistor to Program the Oscillator T Frequency. The programming frequency range is 300kHz to 2MHz • OSC R T MODE/SYNC (Pin 2): ...
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W BLOCK DIAGRA SW1 2. SUPPLY CURRENT LIMIT + – 2.7A UVLO + – 2. OSC 1 SYNC SLEEP MODE/SYNC Burst Mode ...
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LTC3440 U OPERATIO The LTC3440 provides high efficiency, low noise power for applications such as portable instrumentation. The LTC proprietary topology allows input voltages above, below or equal to the output voltage by properly phasing the output switches. The error ...
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U OPERATIO 75% D MAX BOOST A ON, B OFF BOOST REGION PWM CD SWITCHES D MIN BOOST BUCK/BOOST REGION FOUR SWITCH PWM D MAX BUCK D ON, C OFF BUCK REGION PWM AB SWITCHES 0% DUTY CYCLE Figure 2. ...
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LTC3440 U OPERATIO voltage from the error amp to determine the control mode, therefore full-time 4-switch mode is required to maintain the Buck/Boost function. The efficiency below 1mA becomes dominated primarily by the quiescent current and not the peak efficiency. ...
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U OPERATIO SOFT-START The soft-start function is combined with shutdown. When the SHDN/SS pin is brought above typically 1V, the IC is enabled but the EA duty cycle is clamped from the SOFT-START CLAMP ...
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LTC3440 U U APPLICATIO S I FOR ATIO Ripple = allowable inductor current ripple (e.g., 0 minimum input voltage, V IN(MIN maximum input voltage, V IN(MAX output voltage, V OUT I = ...
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U U APPLICATIO S I FOR ATIO Output Voltage > 4.3V A Schottky diode from OUT voltages over 4.3V. The diode must be located as close to the pins as possible in order to reduce the peak ...
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LTC3440 U U APPLICATIO S I FOR ATIO 1 ≈ f POLE 1 π • • • • Which is extremely close ZERO 1 π 2 • • ...
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U U APPLICATIO S I FOR ATIO Simple Average Input Current Control A simple average current limit circuit is shown in Figure 10. Once the input current of the IC is above approximately 1A, Q1 will start sourcing current into ...
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LTC3440 U TYPICAL APPLICATIO S 3-Cell to 5V Boost Converter with Output Disconnect 3 SW1 V = 2. SHDN/ MODE/SYNC * C1 C3 CELLS 10μF 0.1μ ...
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U TYPICAL APPLICATIO S WCDMA Power Amp Power Supply with Dynamic Voltage Control L1 3.3μ SW1 SW2 LTC3440 V = 2. OUT 8 9 SHDN/ ...
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LTC3440 PACKAGE DESCRIPTIO 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS Package 10-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # ...
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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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... DC/DC Converter LTC3412 2.5A(I ), 4MHz, Synchronous Step-Down OUT DC/DC Converter LTC3441/LTC3443 1.2A(I ), 1MHz/0.6MHz, Micropower Synchronous OUT Buck-Boost DC/DC Converter 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 ● V OUT 3.3V 220pF ...