LT1370 Linear Technology, LT1370 Datasheet
LT1370
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LT1370 Summary of contents
Page 1
... A 6A high efficiency switch is included on the die, along with all oscillator, control and protection circuitry. The LT1370 typically consumes only 4.5mA quiescent current and has higher efficiency than previous parts. High frequency switching allows for very small inductors to be used ...
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... LT1370 BSOLUTE Supply Voltage ....................................................... 30V Switch Voltage LT1370 ............................................................... 35V LT1370HV .......................................................... 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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... High Clamp Low Clamp 1.5V FB Duty Cycle = 0% 2.7V V 25V 125 C J – (I-Grade) J LT1370 LT1370HVC 125 C J LT1370HVI, – (I-Grade Duty Cycle = 50% Duty Cycle = 80% (Note 1) 2.7V V 25V IN 2.7V V 25V, V 0.6V IN S/S 2.7V V 25V IN 0V S/S 5V ...
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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) LT1370 • G08 100 125 150 LT1370 • G03 V 0.1 REF LT1370 • G06 (FB) 100 125 150 LT1370 • G09 ...
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... See Applications Information. Negative Feedback Input Current vs Temperature NFB NFR –10 –20 –30 –40 –50 –50 50 125 150 – TEMPERATURE ( C) LT1370 • G11 or leave it floating drops below 2.5V. Undervoltage lockout IN pin low. C LT1370 100 125 150 LT1370 • G12 5 ...
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... REF GND SENSE U OPERATION The LT1370 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 ...
Page 7
... 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 LT1370 in an idle mode. ) has three different C ...
Page 8
... LT1370 U U APPLICATIO S I FOR ATIO Shutdown and Synchronization The device has a dual function S/S pin which is used for both shutdown and synchronization. This pin is logic level compatible and can be pulled high, tied to V floating for normal operation. A logic low on the S/S pin activates shutdown, reducing the part’ ...
Page 9
... At 500kHz any polarized capacitor is essentially resistive. To get low ESR takes volume , so physically smaller capacitors have high ESR. The ESR range needed for typical LT1370 applications is 0.025 to 0 typical output capacitor is an AVX type TPS 25V (two each), with a guaranteed ESR less than 0.2 . This is a “ ...
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... LT1370 U U APPLICATIO S I FOR ATIO 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. Capacitors in the range 100 F with an ESR of 0 ...
Page 11
... U U APPLICATIO S I FOR ATIO Layout Considerations For maximum efficiency, LT1370 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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... S/S SW LT1370 NFB MBRS360T3 V GND C C2 0.047 *DALE LPE-5047-100MB + C4 100 F 2 † –V OUT –5V R2 2.49k 1% R3 2.49k 1% LT1370 • TA03 MBRS360T3 V OUT 15V • • 1 –V OUT –15V R4 12. 2.49k 1% LT1370 • TA04 ...
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... C3 R3 0.0047 F 2k † COILCRAFT DO3316P-472 MAX I * OUT ** AVX TPSD107M010R0100 I V OUT IN 2.5A 2.7V 3A 3.3V 3.3A 3.6V LT1370 † V OUT 5V R2 18. 100 F 10V 2 R3 6.19k 1% LT1370 • TA05 OUT V OUT † V OUT 5V R1 18. C4** 100 F 10V 2 R2 6.19k 1% LT1370 • TA06 13 ...
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... HV DIODES 2 10k 10k FB 1N4002 (ALL GND LASER L1 = 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 LT1370 • TA07 ...
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... LT1370 0.165 – 0.180 0.045 – 0.055 (4.191 – 4.572) (1.143 – 1.397) 15 TYP +0.008 0.004 –0.004 ...
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... LT1370 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 1.5A Boost Switching Regulator LT1373 Low Supply Current 250kHz 1.5A Boost Switching Regulator LT1374 500kHz 4.5A Buck Switching Regulator LT1376 500kHz 1 ...