LT1371 Linear Technology, LT1371 Datasheet
LT1371
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LT1371 Summary of contents
Page 1
... A 3A high efficiency switch is included on the die, along with all oscillator, control and protection circuitry. The LT1371 typically consumes only 4mA quiescent current and has higher efficiency than previous parts. High frequency switching allows for very small inductors to be used ...
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... LT1371 BSOLUTE Supply Voltage ....................................................... 30V Switch Voltage LT1371 ............................................................... 35V LT1371HV .......................................................... 42V S/S, SHDN, SYNC Pin Voltage ................................ 30V Feedback Pin Voltage (Transient, 10ms) .............. 10V Feedback Pin Current ........................................... 10mA Negative Feedback Pin Voltage (Transient, 10ms) ............................................. 10V U PACKAGE/ORDER I FOR ATIO FRONT VIEW 7 ...
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... C J – Grade) J 2.7V V 25V S/S SHDN Note 1: For duty cycles (DC) between 50% and 90%, minimum guaranteed switch current is given by I LT1371 MIN TYP MAX UNITS – 2.490 – 2.440 V – 2.490 – 2.410 V – 45 – 30 – ...
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... Error Amplifier Transconductance vs Temperature 2000 1800 1600 1400 1200 1000 800 600 400 200 0 0.9 1.0 –50 – TEMPERATURE ( C) LT1371 • G08 100 125 150 LT1371 • G03 V 0.1 REF LT1371 • G06 (FB) 100 125 150 LT1371 • G09 ...
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... GND: Tie all Ground pins to a good quality ground plane Negative Feedback Input Current vs Temperature NFB NFR –10 –20 –30 –40 –50 –50 50 125 150 – TEMPERATURE ( C) LT1371 • G11 drops below 2.5V. Undervoltage lockout IN pin low. C LT1371 100 125 150 LT1371 • G12 ...
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... REF GND SENSE U OPERATION The LT1371 is a current mode switcher. This means that switch duty cycle is directly controlled by switch current rather than by output voltage. Referring to the block diagram, the switch is turned ON at the start of each oscillator cycle turned OFF when switch current reaches a predetermined level ...
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... Like- wise, a capacitor coupled external clamp will provide soft start. Switch duty cycle goes to zero if the V below the control pin threshold, placing the LT1371 in an idle mode. ) has three different C ...
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... LT1371 U U APPLICATIO S I FOR ATIO Shutdown and Synchronization The 7-pin R and T7 package devices have a dual function S/S pin which is used for both shutdown and synchroni- zation. The SW package device has both a Shutdown (SHDN) pin and a Synchronization (SYNC) pin which can be used separately or tied together. These pins are logic level compatible and can be pulled high, tied to V floating for normal operation ...
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... W U physically smaller capacitors have high ESR. The ESR range needed for typical LT1371 applications is 0.025 to 0 typical output capacitor is an AVX type TPS 25V (2 each), with a guaranteed ESR less than 0.2 . This is a “D” size surface mount solid tantalum capacitor ...
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... LT1371 U U APPLICATIO S I FOR ATIO Output Capacitor Ripple Current (RMS (RMS – DC RIPPLE OUT V OUT = I V OUT DC = Switch Duty Cycle Input Capacitors The input capacitor of a boost converter is less critical due to the fact that the input current waveform is triangular and does not contain large squarewave currents as is found in the output capacitor ...
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... C C margin may be inadequate. Layout Considerations For maximum efficiency, LT1371 switch rise and fall times are made as short as possible. To prevent radiation and high frequency resonance problems, proper layout of the components connected to the switch node is essential. B field (magnetic) radiation is minimized by keeping output diode, Switch pin and output bypass capacitor leads as short as possible ...
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... Application Note 19. Linear Technol- ogy also offers a computer software program, SwitcherCAD, to assist in designing switching converters. In addition, our Applications Department is always ready to lend a helping hand OUT LT1371T7 GND GND TAB 4 LT1371 • F07 SYSTEM GROUND for the life of the ...
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... Single Li-Ion Cell MBRS320T3 L1 18. S/S SW OFF 1% LT1371 + C1** FB 100 F GND V 10V C R2 6.19k C2 1% 0.047 0.0047 F 2k LT1371 • TA06 † * COILCRAFT DO3316P-103 MAX I OUT ** AVX TPSD107M010R0100 I V OUT IN 1.2A 2.7V 1.6A 3.3V 1.8A 3.6V V OUT 15V –V OUT –15V R4 12. ...
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... 10k 10k GND L1=COILTRONICS CTX02-11128 L2=COILCRAFT DO3316P-153 F TYPE MKP-20 47k 5W LASER 1N4002 (ALL COILTRONICS CTX02-11128 190 L2 = GOWANDA GA40-822K 1% Q1 ZETEX ZTX849 0. WIMA 3X 0.15 F TYPE MKP-20 HV DIODES = SEMTECH-FM-50 LASER = HUGHES 3121H-P COILTRONICS (407) 241-7876 LT1371 • TA08 ...
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... TYP 0.050 (1.270) TYP 0.014 – 0.019 (0.356 – 0.482) TYP LT1371 0.165 – 0.180 0.045 – 0.055 (4.191 – 4.572) (1.143 – 1.397) 15 TYP +0.008 0.004 –0.004 0.059 (1.499) +0.203 0.102 – ...
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... LT1371 PACKAGE DESCRIPTION 0.390 – 0.415 (9.906 – 10.541) 0.460 – 0.500 (11.684 – 12.700) 0.040 – 0.060 (1.016 – 1.524) RELATED PARTS PART NUMBER DESCRIPTION LT1171 100kHz 2.5A Boost Switching Regulator ® LTC 1265 12V 1.2A Monolithic Buck Converter LT1302 Micropower 2A Boost Converter LT1372 500kHz 1 ...