LT3980EDE#TRPBF Linear Technology, LT3980EDE#TRPBF Datasheet

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... MSOP and 3mm × 4mm DFN packages with exposed pads for low thermal resistance. L, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...

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... JA JC EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3980EDE#PBF LT3980EDE#TRPBF LT3980IDE#PBF LT3980IDE#TRPBF LT3980EMSE#PBF LT3980EMSE#TRPBF LT3980IMSE#PBF LT3980IMSE#TRPBF LT3980HMSE#PBF LT3980HMSE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T noted. (Note 2) PARAMETER Quiescent Current from BD Feedback Voltage FB Pin Bias Current (Note 3) FB Voltage Line Regulation Error Amp g m Error Amp Gain V Source Current ...

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LT3980 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency 3.3V OUT 12V 24V 48V 400kHz D = DIODES, INC. SBR3U100LP 50 0 ...

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TYPICAL PERFORMANCE CHARACTERISTICS Switch Voltage Drop 700 600 500 400 300 200 100 SWITCH CURRENT (A) 3980 G10 Switching Frequency 1.20 1.15 1.10 1.05 1.00 0.95 0.90 0. 32.4k 0.80 –50 – ...

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LT3980 TYPICAL PERFORMANCE CHARACTERISTICS Boost Diode 1.4 1.2 1.0 0.8 0.6 0.4 0 0.5 1.0 1.5 BOOST DIODE CURRENT (A) Minimum Input Voltage OUT 400kHz TO START RUN 5 ...

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PIN FUNCTIONS (DFN, MSOP) SYNC (Pin 1/Pin 1): This is the external clock synchro- nization input. Ground this pin for low ripple Burst Mode operation at low output loads. Tie to a clock source for synchronization. Clock edges should have ...

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LT3980 OPERATION The LT3980 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by RT, enables an RS fl ip-fl op, turning on the internal power switch. An amplifi er and comparator monitor the current ...

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APPLICATIONS INFORMATION FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resis- tors according to: ⎛ ⎞ V OUT = – 1 ⎜ ...

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LT3980 APPLICATIONS INFORMATION max load the switching frequency (set the minimum switch on time (~200ns). Note that ON(MIN) a higher switching frequency will depress the maximum operating input voltage. Conversely, a lower switching ...

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... For details of maximum output current and discontinuous mode opera- tion, see Linear Technology Application Note 44. Finally, for duty cycles greater than 50 minimum inductance required to avoid subharmonic oscillations. See AN19. ...

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LT3980 APPLICATIONS INFORMATION Low ESR is important, so choose one that is intended for use in switching regulators. The ESR should be specifi the supplier, and should be 0.05Ω or less. Such a capacitor will be larger than ...

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APPLICATIONS INFORMATION Loop compensation determines the stability and transient performance. Designing the compensation network is a bit complicated and the best values depend on the application and in particular the type of output capacitor. A practical approach is to start ...

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LT3980 APPLICATIONS INFORMATION If low quiescent current is not required the LT3980 can operate in pulse-skipping mode. The benefi this mode is that the LT3980 will enter full frequency standard PWM operation at a lower output load current ...

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APPLICATIONS INFORMATION While operating with high boost voltages (>10V important to ensure that the power dissipation from the boost circuit is not too high. See the Typical Performance Characteristics section for the plot, BOOST Pin Current vs Switch ...

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LT3980 APPLICATIONS INFORMATION create a voltage ramp at this pin. Figure 7 shows the start- up and shutdown waveforms with the soft-start circuit. By choosing a large RC time constant, the peak start-up current can be reduced to the current ...

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... LT3980 circuits. However, these capaci- tors can cause problems if the LT3980 is plugged into a live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capacitor, combined with stray inductance in series with the power ...

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... The die temperature is calculated by multiplying the LT3980 power dissipation by the thermal resistance from junction to ambient. Other Linear Technology Publications Application Notes 19, 35 and 44 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1376 data sheet has a more extensive discussion of output ripple, loop compensation and stability testing ...

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TYPICAL APPLICATIONS V IN 6.5V TO 58V TRANSIENT TO 80V 4.7μ 4.3V TO 58V TRANSIENT TO 80V 4.7μF 5V Step-Down Converter RUN/SS BOOST ON OFF LT3980 RT 4.75k PG DA 97.6k SYNC ...

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LT3980 TYPICAL APPLICATIONS 58V TRANSIENT TO 80V 4.7μ 8.6V TO 40V TRANSIENT TO 80V 4.7μF 20 2.5V Step-Down Converter RUN/SS BOOST ON OFF LT3980 RT 8.45k PG DA ...

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TYPICAL APPLICATIONS V IN 15V TO 58V TRANSIENT TO 80V 10μ 3.5V TO 32V 4.7μF 12V Step-Down Converter OFF RUN/SS BOOST LT3980 RT 12k PG DA 60.4k SYNC FB GND 1nF ...

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LT3980 PACKAGE DESCRIPTION 3.30 ±0.05 3.60 ±0.05 2.20 ±0.05 1.70 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 4.00 ±0.10 (2 SIDES) PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF ...

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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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. ...

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... OUT(MIN 3.6V to 36V 0.8V 1.9mA OUT(MIN) Q × 3mm DFN-6 Package : 5.5V to 60V 1.20V 2.5mA OUT(MIN 0909 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2009 < 1μA, < 1μA, SD < 1μA, SD < 1μA, SD < 1μA, SD < 1μ 1μ 2μA, = 10μA, SD < 1μA, SD < ...