LTC3631IMS8E-3.3#TRPBF Linear Technology, LTC3631IMS8E-3.3#TRPBF Datasheet
LTC3631IMS8E-3.3#TRPBF
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LTC3631IMS8E-3.3#TRPBF Summary of contents
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... The LTC3631 is available in the thermally enhanced 3mm × 3mm DFN and MS8E packages. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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... JC EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB orDer inForMaTion LEAD FREE FINISH TAPE AND REEL LTC3631EMS8E#PBF LTC3631EMS8E#TRPBF LTC3631EMS8E-3.3#PBF LTC3631EMS8E-3.3#TRPBF LTFFP LTC3631EMS8E-5#PBF LTC3631EMS8E-5#TRPBF LTC3631IMS8E#PBF LTC3631IMS8E#TRPBF LTC3631IMS8E-3.3#PBF LTC3631IMS8E-3.3#TRPBF LTC3631IMS8E-5#PBF LTC3631IMS8E-5#TRPBF LTC3631EDD#PBF LTC3631EDD#TRPBF LTC3631EDD-3.3#PBF LTC3631EDD-3.3#TRPBF LTC3631EDD-5#PBF LTC3631EDD-5#TRPBF LTC3631IDD#PBF LTC3631IDD#TRPBF LTC3631IDD-3.3#PBF LTC3631IDD-3.3#TRPBF LTC3631IDD-5#PBF LTC3631IDD-5#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges ...
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T SYMBOL PARAMETER Input Supply ( Input Voltage Operating Range IN UVLO V Undervoltage Lockout IN OVLO V Overvoltage Lockout Supply Current (Note 3) Q ...
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LTC3631 Typical perForMance characTerisTics Efficiency vs Load Current OUT OUT V = 12V FIGURE 10 CIRCUIT 36V 24V 0.1 ...
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Typical perForMance characTerisTics Peak Current Trip Threshold vs R ISET 240 V = 10V IN 220 200 180 160 140 120 100 200 400 600 800 1000 ISET 3631 G10 Quiescent Supply ...
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LTC3631 Typical perForMance characTerisTics Soft-Start Waveform OUTPUT VOLTAGE 1V/DIV 3631 G19 C = 0.047µF 5ms/DIV SS pin FuncTions SW (Pin 1): Switch Node Connection to Inductor. This pin connects to the drains of the internal power MOSFET switches. V (Pin ...
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DiagraM 1µA I SET 3 RUN + 5 – 1.2V HYST 7 GND GND 8 9 PEAK CURRENT – COMPARATOR + LOGIC AND SHOOT- THROUGH PREVENTION + REVERSE CURRENT – COMPARATOR VOLTAGE REFERENCE FEEDBACK + COMPARATOR 0.800V + – ...
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LTC3631 operaTion (Refer to Block Diagram) The LTC3631 is a step-down DC/DC converter with internal power switches that uses Burst Mode control, combining low quiescent current with high switching frequency, which results in high efficiency across a wide range of ...
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Block Diagram) then the output voltage will be limited by the ramp rate on the SS pin instead. The internal and external soft-start functions are reset on start-up and after an undervoltage or overvoltage event on the ...
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LTC3631 applicaTions inForMaTion The basic LTC3631 application circuit is shown on the front page of this data sheet. External component selection is determined by the maximum load current requirement and begins with the selection of the peak current programming resistor, ...
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OUT L = 47µH I OPEN SET 600 500 L = 100µH 400 300 L = 220µH 200 L = 470µH 100 INPUT VOLTAGE (V) Figure 2. ...
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LTC3631 applicaTions inForMaTion This formula has a maximum /2. This simple worst-case condition is com- RMS OUT monly used for design because even significant deviations do not offer much relief. Note that ripple current ratings ...
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Output Voltage Programming For the adjustable version, the output voltage is set by an external resistive divider according to the following equation: R1 0.8V • 1+ OUT R2 The resistive ...
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LTC3631 applicaTions inForMaTion The minimum value of these thresholds is limited to the internal V UVLO thresholds that are shown in the IN Electrical Characteristics table. The current that flows through this divider will directly add to the shutdown, sleep ...
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The gate charge current results from switching the gate capacitance of the internal power MOSFET switches. Each time the gate is switched from high to low to high again, a packet of charge, dQ, moves from V ground. ...
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LTC3631 applicaTions inForMaTion The undervoltage lockout requirement on V satisfied with a resistive divider from V HYST pins. Choose and calculate R2 and R3 as follows: 1.21V R2 = • R1= 224k ...
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Typical applicaTions 45V 3.3V, 100mA Regulator with Peak Current Soft-Start, Small Size L1 22µ 4.5V TO 24V C IN LTC3631 1µF RUN SET SS HYST C GND SS 22nF ...
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LTC3631 Typical applicaTions 45V High Efficiency 15V, 20mA Regulator L1 1000µ 15V TO 45V C LTC3631 IN 1µF RUN SET SS HYST GND C : AVX 18125C105KAT2A IN ...
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DescripTion 3.5 ±0.05 1.65 ±0.05 2.10 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF DD Package 8-Lead Plastic ...
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LTC3631 package DescripTion 1.88 ± 0.102 (.074 ± .004) 5.23 (.206) MIN 0.42 ± 0.038 (.0165 ± .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING ...
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... OUT Updated Efficiency Considerations section 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. LTC3631 ...
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... OUT(MIN 0.8V 2.5mA, I < 10µA, OUT(MIN 1.2V 100µA, I < 1µA, OUT(MIN 1.25V 100µA, I < 1µA, OUT(MIN 1.2V 26µA, I < 1µA, OUT(MIN 0.78V 70µA, I < 1µA, OUT(MIN 1010 REV C • PRINTED IN USA LINEAR TECHNOLOGY CORPORA TION 2009 3631fc ...