LT3970EMS-5#PBF Linear Technology, LT3970EMS-5#PBF Datasheet

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... The LT3970 is available in small 10-pin MSOP and 3mm × 2mm DFN packages. L, LT, LTC, LTM, Burst Mode, Linear Technology 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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... LT3970IMS-3.3#TRPBF LT3970HMS-3.3#PBF LT3970HMS-3.3#TRPBF LT3970EDDB-5#PBF LT3970EDDB-5#TRPBF LT3970IDDB-5#PBF LT3970IDDB-5#TRPBF LT3970EMS-5#PBF LT3970EMS-5#TRPBF LT3970IMS-5#PBF LT3970IMS-5#TRPBF LT3970HMS-5#PBF LT3970HMS-5#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Minimum Input Voltage Quiescent Current from V IN LT3970 Feedback Voltage LT3970-3.3 Output Voltage LT3970-5 Output Voltage LT3970 FB Pin Bias Current (Note 3) FB/Output Voltage Line Regulation Switching ...

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LT3970/LT3970-3.3/LT3970-5 ELECTRICAL CHARACTERISTICS Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LT3970E ...

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TYPICAL PERFORMANCE CHARACTERISTICS No-Load Supply Current 15 FRONT PAGE APPLICATION V = 12V 3.3V OUT 576k –50 – 100 125 TEMPERATURE (°C) 3970 ...

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LT3970/LT3970-3.3/LT3970-5 TYPICAL PERFORMANCE CHARACTERISTICS Switch 200mA) CESAT SW vs Temperature 250 200 150 100 –50 – 100 125 150 TEMPERATURE (°C) 3970 G14 Minimum Input Voltage 3.3V OUT 5.0 FRONT PAGE ...

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TYPICAL PERFORMANCE CHARACTERISTICS EN Threshold 1.050 1.025 1.000 0.975 0.950 –50 – 100 125 150 TEMPERATURE (°C) 3970 G23 Switching Waveforms, Burst Mode Operation V SW 5V/DIV I L 100mA/DIV V OUT 5mV/DIV 2μs/DIV FRONT PAGE ...

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LT3970/LT3970-3.3/LT3970-5 PIN FUNCTIONS FB (Pin 1, LT3970 Only): The LT3970 Regulates the FB Pin to 1.21V. Connect the feedback resistor divider tap to this pin. V (Pin 1, LT3970-3.3 and LT3970-5 Only): The LT3970- OUT 3.3 and LT3970-5 regulate the ...

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OPERATION The LT3970 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by RT, sets an RS fl ip-fl op, turning on the internal power switch. An amplifi er and comparator monitor the current fl ...

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LT3970/LT3970-3.3/LT3970-5 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 R1=R2 – 1 1.21 Reference designators refer to the ...

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... For details of maximum output current and discontinu- ous mode operation, see Linear Technology Application Note 44. Finally, for duty cycles greater than 50% (V > 0.5), there is a minimum inductance required to avoid subharmonic oscillations ...

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LT3970/LT3970-3.3/LT3970-5 APPLICATIONS INFORMATION the ripple current. Note that larger input capacitance is required when a lower switching frequency is used (due to longer on-times). If the input power source has high impedance, or there is signifi cant inductance due to ...

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APPLICATIONS INFORMATION operates at a lower current limit during Burst Mode operation, the noise is typically very quiet to a casual ear. If this is unacceptable, use a high performance tantalum or electrolytic capacitor at the output. A fi nal ...

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LT3970/LT3970-3.3/LT3970-5 APPLICATIONS INFORMATION BOOST LT3970 SW GND (4a) For V ≥ 2.2V OUT BOOST LT3970 SW GND (4b) For V < 2.2V; V OUT IN Figure 4. Two ...

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APPLICATIONS INFORMATION LT3970 – R4 Figure 6. Enable Be aware that while V is below 4.2V, the input current IN may rise up to several hundred μA and the part may begin ...

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... If the input supply is poorly controlled or the user will be plugging the LT3970 into an energized supply, the input network should be designed to prevent this overshoot. See Linear Technology Application Note 88 for a complete discussion. High Temperature Considerations For higher ambient temperatures, care should be taken in the layout of the PCB to ensure good heat sinking of the LT3970 ...

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TYPICAL APPLICATIONS 3.3V Step-Down Converter V IN 4.2V TO 40V V BOOST IN LT3970 OFF 2.2μF GND 226k f = 600kHz 3.3V Step-Down Converter V IN 4.2V TO 40V V BOOST IN ...

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LT3970/LT3970-3.3/LT3970-5 TYPICAL APPLICATIONS 12V Step-Down Converter V IN 14V TO 40V V BOOST IN LT3970 OFF 2.2μF GND 226k f = 600kHz 5V Step-Down Converter with Reduced Input Current During Start-Up kΩ ...

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PACKAGE DESCRIPTION 0.64 ±0.05 (2 SIDES) 0.70 ±0.05 2.55 ±0.05 1.15 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 2.39 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE OUTLINE ...

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LT3970/LT3970-3.3/LT3970-5 PACKAGE DESCRIPTION 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR ...

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... Added LT3970-3.3 and LT3970-5 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. LT3970/LT3970-3.3/LT3970-5 ...

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... OUT(MIN 0.8V 75μA, OUT(MIN 0.8V 75μA, I < 1μA, OUT(MIN 0.78V 70μA, I < 1μA, OUT(MIN 0.78V 70μA, I < 1μA, OUT(MIN 1.26V 50μA, I < 1μA, OUT(MIN 1.20V 100μA, I < 1μA, OUT(MIN 3970fa LT 0510 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2009 ...