LTC1265CS Linear Technology, LTC1265CS Datasheet
LTC1265CS
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LTC1265CS Summary of contents
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... The inductor current is user-programmable via an external current sense resistor. Operation up to 700kHz permits the use of small surface mount inductors and capacitors. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. L1 ...
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... OUT C = 390pF 800mA (LTC1265C) T LOAD C = 390pF 800mA (LTC1265I) T LOAD ORDER PART NUMBER 14 SW LTC1265CS 13 PWR PGND LTC1265CS-5 11 SGND LTC1265CS-3.3 10 SHDN LTC1265IS 9 N SENSE = 110 C/W JA MIN TYP MAX UNITS 0.2 1 1.22 1.25 1.28 1.20 1.25 1.30 3.22 3.3 3.40 4 ...
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... I Shutdown Pin Input Current 10 Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note calculated from the ambient temperature T J dissipation P according to the following formulas: D LTC1265CS, LTC1265CS-3.3, LTC1265CS- • 110 C/ TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current ...
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LTC1265/LTC1265-3.3/LTC1265 TYPICAL PERFOR A CE CHARACTERISTICS DC Supply Current 2.1 DOES NOT INCLUDE GATE CHARGE 1.8 ACTIVE MODE 1.5 1.2 0.9 0.6 0.3 SLEEP MODE INPUT VOLTAGE (V) 1265 ...
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CTIO AL DIAGRA SLEEP + S – V TH2 V TH1 OPERATIO (Refer to Functional Diagram) The LTC1265 uses a constant off-time architecture to switch its internal P-channel power MOSFET. The off time ...
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LTC1265/LTC1265-3.3/LTC1265-5 U OPERATIO (Refer to Functional Diagram) capacitor discharges past V until its voltage drops TH1 below V . Comparator S then trips and a sleep signal is TH2 generated. The circuit now enters into sleep mode with the power ...
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U U APPLICATIO S I FOR ATIO Under short-circuit condition, the peak inductor current is determined by: = 150mV I (Amps) SC(PK) R SENSE In this condition, the LTC1265 automatically extends the off time of the P-channel MOSFET to allow ...
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LTC1265/LTC1265-3.3/LTC1265 APPLICATIO S I FOR ATIO P-channel switch duty cycle. At high input voltages, the diode conducts most of the time the diode conducts only a small fraction of the time. The most stressful condition for ...
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U U APPLICATIO S I FOR ATIO The output, Pin N-channel open drain that goes low when the battery voltage is below the threshold set by R3 and R4. In shutdown, the comparator is disabled and Pin ...
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LTC1265/LTC1265-3.3/LTC1265 APPLICATIONS INFORMATION output voltage can potentially float above the maximum allowable tolerance. To prevent this from occuring, a resistor must be connected between V with a value low enough to sink the maximum possible leakage current. THERMAL ...
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U U APPLICATIO S I FOR ATIO 1000pF 4 3900pF Figure 6. LTC1265 Layout Diagram (See Board Layout Checklist) Troubleshooting Hints Since efficiency is critical to LTC1265 applications very important to ...
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LTC1265/LTC1265-3.3/LTC1265 APPLICATIO S I FOR ATIO (a) POORLY DECOUPLED LTC1265 Design Example As a design example, assume 0.8A and f = 250kHz. With this information we can easily calculate all the important ...
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U TYPICAL APPLICATIO 270pF 3900pF 1k * AVX TPSD107K010 ** AVX TPSE227K010 † COILCRAFT D03316-473 †† DALE WSL2010-0.1-1% * AVX TPSD226K025 ** AVX TPSD107K010 † L1 SELECTION MANUFACTURER PART NO. COILCRAFT DO3316-473 COILTRONICS CTX50-4 LPT4545-500LA DALE ...
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LTC1265/LTC1265-3.3/LTC1265-5 U TYPICAL APPLICATIO S V (V) I (mA) IN OUT(MAX) 3.5V TO 7.5V 3.5 240 4.0 275 5.0 365 6.0 490 7.0 610 7.5 665 75pF L1A L1B 3 2 TOP VIEW 3300pF • L1A L1B SANYO ...
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... SENSE 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC1265/LTC1265-3.3/LTC1265-5 2.5mm Max Height 5V-to-3.3V (500mA) ...
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... TRICKLE CHARGE LTC1265 TA08 0.337 – 0.344* (8.560 – 8.738 0.150 – 0.157** (3.810 – 3.988 16V IN 20V 400mA, MS8 Q , MS8 IN to 500mA, 2.65V to 8.5V V OUT IN IN 126535fb LT/LCG 0800 2K REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1995 S14 1298 ...