LTC3609EWKG#PBF Linear Technology, LTC3609EWKG#PBF Datasheet

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... Point of Load Regulation n Distributed Power Systems n L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6100678, 6580258, 5847554, 6304066. Typical applicaTion ...

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... Storage Temperature Range ................... –55°C to 125°C orDer inForMaTion LEAD FREE FINISH TAPE AND REEL LTC3609EWKG#PBF LTC3609EWKG#TRPBF LTC3609IWKG#PBF LTC3609IWKG#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. ...

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SYMBOL PARAMETER Main Control Loop SV Operating Input Voltage Range IN I Input DC Supply Current Q Normal Shutdown Supply Current V Feedback Reference Voltage FB ∆V Feedback Voltage Line Regulation FB(LINEREG) ∆V Feedback Voltage Load Regulation FB(LOADREG) ...

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LTC3609 elecTrical characTerisTics junction temperature range, otherwise specifications are at T SYMBOL PARAMETER Internal V Regulator CC V Internal V Voltage INTVCC CC ∆V Internal V Load Regulation LDO(LOADREG EXTV Switchover Voltage EXTVCC CC ∆V EXTV Switch Drop Voltage EXTVCC CC ∆V EXTV Switchover Hysteresis ...

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Typical perForMance characTerisTics Efficiency vs Load Current 100 OUT 3.3V OUT V = 2.5V 60 OUT V = 1.8V OUT 1.5V OUT V = 1.2V OUT OUT ...

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LTC3609 Typical perForMance characTerisTics On-Time vs Temperature 300 I = 30µA ION VON 250 200 150 100 50 0 –50 – 100 TEMPERATURE (°C) 3609 G13 Maximum Valley Current Limit vs Temperature ...

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Typical perForMance characTerisTics INTV Load Regulation CC 0.30 0.20 0.10 0 –0.10 –0.20 –0.30 –0. INTV LOAD CURRENT (mA) CC 3609 G22 FCB Pin Current vs Temperature 0 –0.25 –0.50 –0.75 –1.00 –1.25 –1.50 –50 – ...

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LTC3609 pin FuncTions PV (Pins 48, 49, 50, 51, 52, 53): IN Main Input Supply. Decouple this pin to power PGND with the input capacitance (Pins 8, 33, 41, 42, 43, 44, 45, 46, 47, 55): Switch Node Connection to the Inductor. The (–) terminal of the bootstrap capacitor also connects ...

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FuncTional DiagraM 0.7V 2.4V V VON t = (10pF ION S 20k + + I CMP – – 1.4V V RNG 17 (0 0.7V 1 240k Q2 ...

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LTC3609 operaTion Main Control Loop The LTC3609 is a high efficiency monolithic synchronous, step-down DC/DC converter utilizing a constant on-time, current mode architecture. It operates from an input voltage range 32V/36V maximum and provides a regulated output voltage at ...

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The basic LTC3609 application circuit is shown on the front page of this data sheet. External component selection is primarily determined by the maximum load current. The LTC3609 uses the on-resistance of the synchronous power MOSFET for determining ...

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LTC3609 applicaTions inForMaTion Because the voltage at the I pin is about 0.7V, the cur- ON rent into this pin is not exactly inversely proportional especially in applications with lower input voltages correct for this ...

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R VON1 30k V OUT C VON R VON2 0.01µF 100k (2a) R VON1 3k V OUT C R VON VON2 0.01µF 10k 10k INTV 2N5087 C C (2b) Figure 2. Correcting Frequency Shift with Load Current Changes Minimum Off-time and Dropout Operation ...

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LTC3609 applicaTions inForMaTion Once the value for L is known, the type of inductor must be selected. High efficiency converters generally cannot afford the core loss found in low cost powdered iron cores. A variety of inductors designed for high ...

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V . Tying the FCB pin below the 0.6V IN threshold forces continuous synchronous operation, al- lowing current to reverse at light loads and maintaining high frequency operation. In addition to providing a logic input ...

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LTC3609 applicaTions inForMaTion The EXTV pin can be used to provide MOSFET gate drive CC and control power from the output or another external source during normal operation. Whenever the EXTV pin is above 4.7V the internal 5V regulator is ...

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RUN/ (5a) Figure 5. RUN/SS Pin Interfacing with Latchoff Defeated Efficiency Considerations The percent efficiency of a switching regulator is equal to the output power divided by the input power times 100 often ...

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LTC3609 applicaTions inForMaTion Design Example As a design example, take a supply with the following specifications 32V (12V nominal 2.5V ± 550kHz. First, calculate the OUT(MAX) timing resistor with ...

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How to Reduce SW Ringing As with any switching regulator, there will be voltage ring- ing on the SW node, especially for high input voltages. The ringing amplitude and duration is dependent on the switching speed (gate drive), layout (parasitic inductance) and ...

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LTC3609 applicaTions inForMaTion C OUT OUT KEEP POWER GROUND AND SIGNAL GROUND SEPARATE. CONNECT AT ONE POINT VCC ...

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Typical applicaTions GND OUT 41 1. 0.5µH OUT1 43 100µ GND ...

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LTC3609 Typical applicaTions GND OUT 41 1. OUT1 0.8µH 100µ GND ...

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Typical applicaTions GND OUT 41 1. OUT1 0.47µH 100µ GND ...

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LTC3609 package DescripTion 7.00 BSC PAD 1 4 CORNER aaa C 2x TOP VIEW 9 7.50 ± 0.05 2.90 REF 2.625 REF 0.50 BSC PIN 1 3.20 ± 0.10 2.025 ± 0.10 3.40 REF 2.925 ± 0.10 1.00 REF 4.275 ...

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... Updated SW voltage range in Absolute Maximum Ratings. Note 4 updated. 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC3609 ...

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... I = 900µA, I <15µA, OUT(MIN 2.25V to 5.5V 0.8V 64µA, I OUT(MIN 2.5V to 5.5V 0.6V 450µA, I OUT(MIN 2.25V to 5.5V 0.8V 380µA, I OUT(MIN 0610 REV B • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2008 CC JP1 <1µA, <1µA, <1µA, 3609fb ...