lm2655mtcx-adj National Semiconductor Corporation, lm2655mtcx-adj Datasheet
lm2655mtcx-adj
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lm2655mtcx-adj Summary of contents
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... DC-DC converters. A programmable soft-start feature limits start up current surges and provides a means of se- quencing multiple power supplies. Typical Application © 2005 National Semiconductor Corporation Features n Ultra-high efficiency 14V input voltage range n Internal high-side MOSFET with low R ...
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Connection Diagram Block Diagram www.national.com 16-Lead TSSOP (MTC) 10128403 Top View Order Number LM2655MTC-ADJ See NS Package Number MTC16 2 10128404 ...
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... LDR Low-side FET gate drive pin. 13 GND Power ground. 14-16 PV Main power supply input pin. Connected to the drain of the internal high-side MOSFET. IN Ordering Information Supplied as 1000 units Tape and Reel LM2655MTC-3.3 LM2655MTC-ADJ Function Supplied as 3000 units, Tape and Reel LM2655MTCX-3.3 LM2655MTCX-ADJ 3 www.national.com ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage ( Supply Voltage ( Feedback Pin Voltage V Voltage, (Note ...
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All Output Voltage Versions Electrical Characteristics Specifications with standard typeface are for T Range 10V unless otherwise specified. IN Symbol Parameter I Quiescent Current Q I Quiescent Current in QSD Shutdown Mode R Switch ON Resistance DS(ON) R ...
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All Output Voltage Versions Electrical Characteristics Specifications with standard typeface are for T Range 10V unless otherwise specified. IN Symbol Parameter T Thermal Shutdown SD_HYST Hysteresis Temperature Low-side Driver (LDR) Parameters Specifications with standard typeface are for T ...
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Typical Performance Characteristics Efficiency vs Load Current ( 3.3V) IN OUT Junction Temperature QSD (I LOAD 10128405 10128407 Frequency vs Junction Temperature 10128409 7 Efficiency ...
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Typical Performance Characteristics R + Bond Wire Resistance vs SW(ON) Input Voltage (Note 10) (I Current Limit vs Input Voltage (Synchronous) Current Limit vs Junction Temperature ( 3.3V) IN OUT www.national.com (Continued) = 1.5A) Junction Temperature ...
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Operation The LM2655 is a constant frequency (300kHz), current- mode PWM switcher that can be operated synchronously or asynchronously. SYNCHRONOUS OPERATION A converter is said synchronous operation when a MOSFET is used in place of the catch ...
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Design Procedure (Continued) ment. A reasonable value is setting the ripple current to be 30% of the DC output current. Since the ripple current in- creases with the input voltage, the maximum input voltage is always used to determine the ...
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Design Procedure (Continued) within 30ns. An input capacitance of less than 1000pF is recommended. Several suitable MOSFETs are shown in Table 1. EXTERNAL SCHOTTKY DIODE (Syncronous) A Schottky diode is recommended to prevent the intrinsic body diode of the low-side ...
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Design Procedure (Continued) In some applications, the ESR zero Then needed to introduce ESR zero 1/(2π The rule of thumb is to ...
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Application Circuits (Continued) OBTAINING OUTPUT VOLTAGES OF LESS THAN 1.25V Some applications require output voltages less than 1.25V. The circuit shown in Figure 5 will allow the LM2655 to do such a conversion. By referencing the two feedback resis- > ...
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Typical PC Board Layout: (2X Size) www.national.com Schematic for the Typical Board Layout Component Placement Guide 10128427 Component Side PC Board Layout 14 10128425 10128426 ...
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Typical PC Board Layout: (2X Size) (Continued) 10128428 Solder Side PC Board Layout 15 www.national.com ...
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... Français Tel: +33 ( 8790 16-Lead TSSOP (MTC) NS Package Number MTC16 Order Number LM2655MTC-ADJ LM2655MTCX-ADJ LM2655MTC-3.3 LM2655MTCX-3 critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...