LTC1874EGN Linear Technology, LTC1874EGN Datasheet
LTC1874EGN
Specifications of LTC1874EGN
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LTC1874EGN Summary of contents
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... In shutdown, each controller draws a mere 8 A. High constant operating frequency of 550kHz allows the use of small external inductors. The LTC1874 is available in a small footprint 16-lead narrow SSOP. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. R1 LTC1874 0.04 ...
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... Note 5: Each controller in the LTC1874 is individually tested in a feedback loop that servos V Note 6: Peak current sense voltage is reduced dependent upon duty cycle to a percentage of value as given in Figure 2. and power INFORMATION TOP VIEW ORDER PART NUMBER 16 PV IN1 15 PGATE1 LTC1874EGN 14 PGND1 13 I /RUN1 FB2 11 GND2 GN PART MARKING – 10 SENSE2 9 ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Reference Voltage vs Temperature 825 V = 4.2V IN 820 815 810 805 800 795 790 785 780 775 –55 –35 – 105 125 TEMPERATURE ( C) 1874 G01 Maximum ...
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LTC1874 PIN FUNCTIONS V (Pin 1): Main Supply Pin for Controller #1. This pin IN1 delivers the Input DC Supply Current (listed in the Electri- cal Characteristics table) plus a small amount of logic switching current. Must ...
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U U FUNCTIONAL DIAGRA – V SENSE1 IN1 1 2 OSC FREQ FOLDBACK SHORT-CIRCUIT 0.3V – GND1 3 – V SENSE2 IN2 9 10 GND2 11 W Controller # CMP – SLOPE COMP – + ...
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LTC1874 U OPERATIO (Refer to Functional Diagram) The LTC1874 is a dual, constant frequency current mode switching regulator. The two switching regulators func- tion identically but independent of each other. The follow- ing description of operation is written for a ...
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U OPERATIO Slope Compensation and Inductor’s Peak Current The inductor’s peak current is determined by: V – ITH SENSE when the controller is operating below 40% duty cycle. However, once the duty cycle ...
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LTC1874 U U APPLICATIO S I FOR ATIO I = 0.4(I ). Remember, the maximum I RIPPLE OUT(MAX) occurs at the maximum input voltage. In Burst Mode operation on an LTC1874 controller, the ripple current is normally set such that ...
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U U APPLICATIO S I FOR ATIO short-circuited. Under this condition the diode must safely handle I at close to 100% duty cycle. Therefore PEAK important to adequately specify the diode peak current and average power dissipation so ...
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LTC1874 U U APPLICATIO S I FOR ATIO Low Supply Operation Although the controller can function down to approxi- mately 2.0V, the maximum allowable output current is reduced when V decreases below 3V. Figure 3 shows the IN amount of ...
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... Figure 6. LTC1874 Layout Diagram (See PC Board Layout Checklist) 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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... Step-Down Switching Regulators LTC1772 Constant Frequency Current Mode Step-Down DC/DC Controller LTC1773 Synchronous Step-Down Controller LTC1877/LTC1878 Low Voltage, Monolithic Synchronous Step-Down Regulator trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 12 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com R1 LTC1874 ...