LTC1475IS8#TR Linear Technology, LTC1475IS8#TR Datasheet
LTC1475IS8#TR
Specifications of LTC1475IS8#TR
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LTC1475IS8#TR Summary of contents
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... A low-battery detector that remains functional in shutdown is provided . The LTC1474/LTC1475 series availability in 8-lead MSOP and SO packages and need for few additional components provide for a minimum area solution. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. LOW BATTERY OUT 7 V ...
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LTC1474/LTC1475 ABSOLUTE MAXIMUM Input Supply Voltage (V ).........................– 0.3V to 20V IN Switch Current (SW, SENSE) .............................. 750mA Switch Voltage (SW) ............. ( (Adjustable Versions) ..........................– 0.3V to 12V FB V (Fixed Versions) ................................ –0.3V ...
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ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER V Feedback Voltage FB LTC1474/LTC1475 V Regulated Output Voltage OUT LTC1474-3.3/LTC1475-3.3 LTC1474-5/LTC1475-5 I Feedback Current FB LTC1474/LTC1475 Only I No Load Supply Current (Note 3) SUPPLY V Output Voltage Line Regulation OUT Output Voltage Load Regulation ...
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LTC1474/LTC1475 W U TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Input Voltage 100 FIGURE 1 CIRCUIT L: CDRH73-101 25mA LOAD I = 200mA LOAD 1mA LOAD INPUT ...
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PIN FUNCTIONS V /V (Pin 1): Feedback of Output Voltage. In the fixed OUT FB versions, an internal resistive divider divides the output voltage down for comparison to the internal 1.23V refer- ence. In the adjustable versions, ...
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LTC1474/LTC1475 U OPERATIO (Refer to Functional Diagram) The LTC1474/LTC1475 are step-down converters with internal power switches that use Burst Mode operation to keep the output capacitor charged to the proper output voltage while minimizing the quiescent current. Burst Mode operation ...
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U U APPLICATIONS INFORMATION The basic LTC1474/LTC1475 application circuit is shown in Figure 1, a high efficiency step-down converter. External component selection is driven by the load requirement and begins with the selection of R SENSE known, L can be ...
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LTC1474/LTC1475 APPLICATIONS INFORMATION If the L calculated is not practical, a larger I MIN be used. Although the above equation provides the mini- mum, better performance (efficiency, line/load regulation, noise) is usually gained with higher values. At ...
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U U APPLICATIONS INFORMATION C and C Selection IN OUT At higher load currents, when the inductor current is continuous, the source current of the P-channel MOSFET is a square wave of duty cycle V OUT voltage transients, a low ...
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LTC1474/LTC1475 U U APPLICATIONS INFORMATION small that this loss is negligible at loads above a milliamp but at no load accounts for nearly all of the loss. The second component, the gate charge current, results from switching the gate capacitance ...
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U U APPLICATIONS INFORMATION LTC1475 Pushbutton On/Off and Microprocessor Interface The LTC1475 provides pushbutton control of power on/off for use with handheld products. A momentary ground on the ON pin sets an internal S/R latch to run mode while a ...
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LTC1474/LTC1475 U U APPLICATIONS INFORMATION with a built-in internal disconnect. The user needs to assess his/her application to determine whether this situ- ation could occur. If so, additional protection is necessary. Prevention against latchup can be accomplished by sim- ply ...
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U U APPLICATIONS INFORMATION V OUT Figure 9. LTC1474/LTC1475 Layout Diagram (See Board Layout Checklist) 5. Are the signal and power grounds segregated? The signal ground consists of the (–) plate of C the LTC1474/LTC1475 and the resistive divider. The ...
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LTC1474/LTC1475 U TYPICAL APPLICATIONS V IN 3.5V TO 18V + † 4 35V * SUMIDA CDRH73-271 ** 3 PARALLEL STANDARD RESISTORS PROVIDE LEAST EXPENSIVE SOLUTION (SEE R SELECTION SECTION) SENSE † AVX TPSC475M035 †† AVX ...
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U TYPICAL APPLICATIONS F** 16V 6 3 100k 8 RUN * COILTRONICS CTX200-4 ** AVX TPSC226M016 † AVX TPSC106M025 †† AVX TPSD226M025 V IN 3.5V TO 12V + 10 F** 25V 6 100k ...
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LTC1474/LTC1475 U TYPICAL APPLICATIONS V IN 3.5V TO 12V + 10 F** 25V †† TP0610 ON/OFF 10M * SUMIDA CDRH74-101 ** AVX TPSC106M025 † AVX TPSC336M010 †† RUN: ON/OFF = 0, SHUTDOWN: 0N/OFF = 18V ...
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U TYPICAL APPLICATIONS 18V + † 4.7 F 35V * SUMIDA CDRH73-101 † AVX TPSC475M035 †† AVX TPSC107M006 Figure 16. High Efficiency 3.3V Regulator with Low Battery Lockout V IN 5.7V TO 18V + 4.7 F** ...
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LTC1474/LTC1475 PACKAGE DESCRIPTION 0.007 (0.18) * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...
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... F19 COMMENTS Max Q Linear Regulator Selectable I = 300mA or 600mA PEAK Burst Mode Operation, Internal MOSFET 500kHz, Small Inductor, High Efficiency Switchers, 1.5A Switch I = 2.8 A Max 1.5 A Max Q Linear Regulator Q(MIN) sn14745 14745fas LT/TP 0398 4K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1997 ...