LTC1624CS LINER [Linear Technology], LTC1624CS Datasheet
LTC1624CS
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LTC1624CS Summary of contents
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FEATURES N-Channel MOSFET Drive Implements Boost, Step-Down, SEPIC and Inverting Regulators Wide V Range: 3.5V to 36V Operation IN Wide V Range: 1.19V to 30V in Step-Down OUT Configuration 1% 1.19V Reference Low Dropout Operation: 95% Duty Cycle 200kHz Fixed ...
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... IN I /RUN, V Voltages ............................ 2.7V to – 0. Peak Driver Output Current < (TG) .................... 2A Operating Temperature Range LTC1624CS ............................................ LTC1624IS ......................................... – Junction Temperature (Note 1)............................. 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER Main Control Loop ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Load Current V = 3.3V OUT 100 V = 3.3V OUT R = 0.033 SENSE 10V 0.001 0.01 0.1 1 ...
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LTC1624 W U TYPICAL PERFORMANCE CHARACTERISTICS V vs Output Current ITH 2.4 ACTIVE MODE 1.2 0.8 SHUTDOWN OUT(MAX) OUT(MAX) I OUT (a) 1624 G01 Frequency vs Feedback Voltage 250 200 150 100 0.25 ...
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PIN FUNCTIONS TG (Pin 6): High Current Gate Drive for Top N-Channel MOSFET. This is the output of a floating driver with a voltage swing equal to INTV superimposed on the CC switch node voltage SW. BOOST ...
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LTC1624 U U FUNCTIONAL DIAGRA 6 W (Shown in a step-down application) ...
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U U APPLICATIONS INFORMATION The LTC1624 can be used in a wide variety of switching regulator applications, the most common being the step- down converter. Other switching regulator architectures include step-up, SEPIC and positive-to-negative converters. The basic LTC1624 step-down application ...
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LTC1624 U U APPLICATIONS INFORMATION Step-Down Converter: Power MOSFET Selection One external N-channel power MOSFET must be selected for use with the LTC1624 for the top (main) switch. The peak-to-peak gate drive levels are set by the INTV voltage. This ...
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U U APPLICATIONS INFORMATION monly used for design because even significant deviations do not offer much relief. Note that capacitor manufacturer’s ripple current ratings are often based on only 2000 hours of life. This makes it advisable to further derate ...
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LTC1624 U U APPLICATIONS INFORMATION pin through a small Schottky diode (like a Central CMDSH- shown in Figure 10. However, for OUT 3.3V and other lower voltage regulators, additional cir- cuitry is required to derive boost supply ...
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U U APPLICATIONS INFORMATION what is limiting the efficiency and which change would produce the most improvement. Percent efficiency can be expressed as: %Efficiency = 100% – ( ...) where L1, L2, etc. are the ...
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LTC1624 U U APPLICATIONS INFORMATION with C , causing a rapid drop in V OUT deliver enough current to prevent this problem if the load switch resistance is low and it is driven quickly. The only solution is to limit ...
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U U APPLICATIONS INFORMATION 100 resistor in series with the SENSE cancels the internal offset in current comparator I to Functional Diagram). This comparator in conjunction with the voltage on the I /RUN pin determines when to TH enter into ...
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LTC1624 U U APPLICATIONS INFORMATION Boost Converters: Power MOSFET Selection One external N-channel power MOSFET must be selected for use with the LTC1624 for the switch. In boost applica- tions the source of the power MOSFET is grounded along with ...
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U U APPLICATIONS INFORMATION Allowing a margin for variations in the LTC1624 (without considering variation assuming 30% ripple SENSE current in the inductor, yields MIN 100 mV R SENSE OUT OUT MAX ...
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LTC1624 U U APPLICATIONS INFORMATION identical voltages are applied to L1 and L2 throughout the switching cycle. By making and wound on the same core the input ripple is reduced along with cost and size. All SEPIC ...
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U U APPLICATIONS INFORMATION 10 H inductance is obtained with a current rating of 4A. Splitting the two windings creates two 10 H inductors with a current rating of 2A each. Therefore substitute (2)( for L ...
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LTC1624 U U APPLICATIONS INFORMATION that the voltage across C1 is constant such that V at full load over the entire V range. Assuming the enegry IN storage in the coupling capacitor C1 must be equal to the enegry stored ...
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U U APPLICATIONS INFORMATION V IN where MAX OUT MAX is the temperature dependency of R constant inversely related to the gate drive current. The maximum switch current occurs at V switch current ...
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LTC1624 U U APPLICATIONS INFORMATION Positive-to-negative converters have high ripple current in both the input and output capacitors. For long capacitor lifetime, the RMS value of this current must be less than the high frequency ripple rating of the capacitor. ...
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U TYPICAL APPLICATIONS 100pF 4 BOLD LINES INDICATE HIGH CURRENT PATHS Figure 9. LTC1624 Layout Diagram (See Board Layout Checklist 560pF R C 4.7k 100pF *COILTRONICS CTX10-4 Figure 10. 5V/3A Converter ...
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LTC1624 U TYPICAL APPLICATIONS C C 470pF R C 6.8k 100pF *SUMIDA CDR105B-100 C C 470pF R C 6.8k 100pF *SUMIDA CDRH125-470 1 SENSE 330pF 3.3k 100pF 4 GND *SUMIDA CDRH125-220 ...
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U TYPICAL APPLICATIONS 1 SENSE 2 I /RUN 330pF 4.7k 100pF 4 GND *COILTRONICS CTX20 SHUTDOWN M3 TP0610L M2 VN2222 R3 100k *COILCRAFT DO5022P-333 C C 470pF R ...
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LTC1624 U TYPICAL APPLICATIONS 1 – SENSE 2 BOOST I /RUN LTC1624 330pF 100pF 6.8k 4 GND * COILTRONICS CTX20-4 Figure 17. 5V/1A SEPIC Converter with Output Derived Boost Voltage V IN ...
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U TYPICAL APPLICATIONS V IN 20V TO + 32V C C 820pF 13.3k 6. KEMET T495X226M035AS SANYO 100MV100GX OUT D1 = MOTOROLA MBRS1100 15V C C 4700pF ...
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LTC1624 U TYPICAL APPLICATIONS V IN 13V TO + 28V IN1 IN2 22 F 35V 2 R 0.033 LTC1624 1 C SENSE C 330pF GND C 100pF ...
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U TYPICAL APPLICATIONS C C 680pF R C 100pF 3.3k * PANASONIC 12TS-7ROLB ** SILICONIX SUD50N03-10 PACKAGE DESCRIPTION 0.010 – 0.020 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 – 0.050 0.406 – 1.270 * DIMENSION DOES NOT ...
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LTC1624 U TYPICAL APPLICATION C3, 0.033 820pF 6.8k 20k 100pF KEMET T495D107M010AS AVX TPSV477M006R0055 OUT D1 = MOTOROLA MBRB2515L ...