LTC1649CS#PBF Linear Technology, LTC1649CS#PBF Datasheet
LTC1649CS#PBF
Specifications of LTC1649CS#PBF
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LTC1649CS#PBF Summary of contents
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... The LTC1649 uses a 200kHz switching frequency and voltage mode control, minimizing external component count and size. Shutdown mode drops the quiescent current to below 10 A. The LTC1649 is available in the 16-pin narrow SO package. , LTC and LT are registered trademarks of Linear Technology Corporation Q1 ...
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LTC1649 ABSOLUTE MAXIMUM (Note 1) Supply Voltage V IN ........................................................................................... V CC ........................................................................................... P VCC1, 2 ................................................................................ Input Voltage I FB ....................................................................... + – ................................................ All Other Inputs ....................... – 0. Operating ...
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ELECTRICAL CHARACTERISTICS Note 1: Absolute Maximum Ratings are those values beyond which the life of a part may be impaired. Note 2: All currents into device pins are positive; all currents out of device pins are negative. All voltages are ...
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LTC1649 PIN FUNCTIONS G1 (Pin 1): Driver Output 1. Connect this pin to the gate of the upper N-channel MOSFET, Q1. This output will swing from P to GND. G1 will always be low when G2 is ...
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W BLOCK DIAGRA V IN DELAY SHDN 50 s COMP LIM + I MAX 12 A TEST CIRCUIT V IN 3.3V MBR0530 22 SHDN + 7. 0.01 F ...
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LTC1649 U U APPLICATIONS INFORMATION OVERVIEW The LTC1649 is a voltage feedback PWM switching regu- lator controller (see Block Diagram) designed for use in high power, low input voltage step-down (buck) convert- ers. It includes an onboard PWM generator, a ...
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U U APPLICATIONS INFORMATION MOSFET Gate Drive The LTC1649 is designed to operate from supplies as low as 2.7V while using standard 5V logic-level N-channel external MOSFETs. This poses somewhat of a challenge— from as little as 2.7V, the LTC1649 ...
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LTC1649 U U APPLICATIONS INFORMATION EXTERNAL COMPONENT SELECTION Power MOSFETs Two N-channel power MOSFETs are required for most LTC1649 circuits. These should be selected primarily by on-resistance considerations; thermal dissipation is often a secondary concern in high efficiency designs. The ...
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U U APPLICATIONS INFORMATION ages and expected loads may require different values. Once the required value is known, the inductor core type can be chosen based on peak current and efficiency requirements. Peak current in the inductor will be equal ...
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LTC1649 U U APPLICATIONS INFORMATION tors that work well in LTC1649 applications. A common way to lower ESR and raise ripple current capability is to parallel several capacitors. A typical LTC1649 application might require an input capacitor with a 5A ...
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U U APPLICATIONS INFORMATION The CP pin can typically supply 50mA at 5V, adequate OUT to power the V and PV pins. This supply can also used to power external circuitry, but any additional current drawn from ...
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LTC1649 U U APPLICATIONS INFORMATION The LTC1649 detects the output current by watching the voltage at I while Q1 is ON. The I FB LIM this voltage to the voltage at I MAX state, Q1 has a known resistance; by ...
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U U APPLICATIONS INFORMATION resume normal operation. The CP OUT lated shutdown, and can be used as a keep-alive supply for external circuitry if desired. Note that any current drawn from the CP pin adds to the ...
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LTC1649 U U APPLICATIONS INFORMATION and output capacitors, the source of Q2, the LTC1649 GND pin, the output return and the input supply return all clustered at one point. Figure modified schematic showing the common connections in ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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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... Operation for Small Circuit 550kHz Operation Output, 10-Lead MSOP 550kHz Operation Output, 16-Lead SSOP Converts 3.3V to Two Output Voltages Using 5V Logic IN N-Channel MOSFETS, Eliminates Need for Auxiliary 5V Supply, >90% Efficiency 1649fa LT/TP 0501 REV A 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 IN ...