LT3581IMSE#PBF Linear Technology, LT3581IMSE#PBF Datasheet

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... TFT-LCD Bias Supplies n Automotive Engine Control Unit (ECU) Power n L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7579816. Typical applicaTion Output Short Protected 12V Boost Converter Operating at 2MHz 1.5µ ...

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... LT3581IDE#PBF LT3581IDE#TRPBF LT3581EMSE#PBF LT3581EMSE#TRPBF LT3581IMSE#PBF LT3581IMSE#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...

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T PARAMETER Minimum Input Voltage V Overvoltage Lockout IN Positive Feedback Voltage Negative Feedback Voltage Positive FB Pin Bias Current Negative FB Pin Bias Current Error Amp Transconductance Error Amp Voltage Gain ...

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LT3581 elecTrical characTerisTics temperature range, otherwise specifications are at T PARAMETER Soft-Start Charge Current Soft-Start Discharge Current Soft-Start High Detection Voltage Soft-Start Low Detection Voltage SHDN Minimum Input Voltage High SHDN Input Voltage Low SHDN Pin Bias Current CLKOUT Output ...

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Typical perForMance characTerisTics Switch Fault Current Limit vs Duty Cycle DUTY CYCLE (%) 3581 G01 Switch Fault Current Limit vs Temperature ...

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LT3581 Typical perForMance characTerisTics Gate Current vs SS Voltage 1000 900 800 700 600 500 400 300 200 100 0 0 0.25 0.50 0.75 1.00 1.25 SS VOLTAGE (V) 3581 G10 SHDN Pin Current 32 28 25° ...

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FuncTions (DFN/MSOP) FB (Pin 1/Pin 1): Positive and Negative Feedback Pin. For a Boost or Inverting Converter, tie a resistor from the FB pin to V according to the following equations: OUT  V – 215 V ...

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LT3581 block DiagraM GATE SOFT- START V C 2.1V + 50mV – 1.8V 250k LDO SHDN + – 1.33V UVLO V IN 1.215V REFERENCE + 14.6k A1 – 14.6k A2 – ...

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DiagraM SS < 50mV | DROPS CAUSING OUT FB < 1.17V (BOOST > 45mV (INVERTING) FAULT1 = OVER VOLTAGE PROTECTION ON V OVER TEMPERATURE (T JUNCTION OVER CURRENT ON SW1 (I > 1.9A MIN) SW1 ...

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LT3581 operaTion OPERATION – OVERVIEW The LT3581 uses a constant-frequency, current mode con- trol scheme to provide excellent line and load regulation. The part’s undervoltage lockout (UVLO) function, together with soft-start and frequency foldback, offers a controlled means of starting ...

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Sample Mode Sample Mode is the mechanism used by the LT3581 to aid in the detection of output shorts. It refers to a state of the LT3581 where the master and slave power switches (Q1 and Q2) are turned ...

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LT3581 operaTion Refer to the State Diagram (Figure 2) for the following description of the LT3581’s operation during a fault event. When a fault is detected, in addition to the FAULT pin being pulled low internally, the LT3581 also disables ...

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BOOST CONVERTER COMPONENT SELECTION D1 L1 20V, 2A 1.5µ OUT1 4.7µF SW1 SW2 FAULT LT3581 FB 4.7µF 100k 130k FAULT GATE CLKOUT SHDN ...

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LT3581 applicaTions inForMaTion SEPIC CONVERTER COMPONENT SELECTION (COUPLED OR UN-COUPLED INDUCTORS 1µF 30V, 2A 3.3µ 16V C IN 22µF L2 SW1 SW2 3.3µH • FAULT LT3581 100k FAULT GATE ...

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DUAL INDUCTOR INVERTING CONVERTER COMPONENT SELECTION (COUPLED OR UN-COUPLED INDUCTORS 1µF 3.3µH 3.3µ 3.3µF 20V SW1 SW2 FAULT LT3581 100k FAULT GATE ENABLE SHDN ...

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LT3581 applicaTions inForMaTion LAYOUT GUIDELINES FOR BOOST, SEPIC, AND DUAL INDUCTOR INVERTING TOPOLOGIES General Layout Guidelines • To optimize thermal performance, solder the exposed ground pad of the LT3581 to the ground plane, with multiple vias around the pad connecting ...

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– RETURN C GROUND DIRECTLY TO LT3581 EXPOSED PAD PIN 17 ADVISED IN TO NOT COMBINE ...

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LT3581 applicaTions inForMaTion where T = Die Junction Temperature perature the final result from the calculations TOTAL shown in Table 4, and θ is the thermal resistance from JA the silicon junction to the ambient air. ...

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Clock Synchronization The operating frequency of the LT3581 can be set by an external source by simply providing a digital clock signal into the SYNC pin (R resistor still required). The LT3581 T will revert to its internal ...

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LT3581 applicaTions inForMaTion • The slave switch, by not performing a current sense operation like the master switch, can sustain fairly large current spikes when the flying capacitors charge up. Since this current spike flows through SW2, it does not ...

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HOT-PLUG The high inrush current associated with hot-plugging V can be largely rejected with the use of an external PMOS. A simple hot-plug controller can be designed by connecting an external PMOS in series with V IN PMOS ...

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LT3581 appenDix SETTING THE OUTPUT VOLTAGE The output voltage is set by connecting a resistor (R from V to the FB pin determined by using the OUT FB following equation – OUT FB R ...

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Minimum Inductance Although there can be a tradeoff with efficiency often desirable to minimize board space by choosing smaller inductors. When choosing an inductor, there are three conditions that limit the minimum inductance: (1) provid- ing adequate ...

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LT3581 appenDix Inductor Current Rating Inductors must have a rating greater than their peak operating current, or else they could saturate and hence contribute to losses in efficiency. The maximum inductor current (considering start-up and steady-state conditions) is given by: ...

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The use of the external PMOS, controlled by the GATE pin, is particularly beneficial when dealing with unintended output shorts in a boost regulator conventional boost regulator, the inductor, Schottky diode, and power switches are susceptible to ...

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LT3581 appenDix found. Figures 15a to 15c illustrate this process for the circuit of Figure 18 with a load current stepped between 540mA and 800mA. Figure 15a shows the transient re- sponse with R equal to 1k. The phase margin ...

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From Figure 16, the DC gain, poles and zeros can be calculated as follows: DC Gain : (Breaking loop at FB pin) ∂ ∂ V ∂ VIN • • DC ...

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LT3581 Typical applicaTions 18.7k C1 4.7µF 10k 43.2k C1: 4.7µF , 16V, X7R, 1206 C2, C3: 4.7µF , 25V, X7R, 1206 D1: DIODES INC. PD3S230H-7 Figure 18. 2MHz 12V, 830mA Boost Converter with Output Short ...

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Typical applicaTions High Efficiency, VFD (Vacuum Fluorescent Display) Power Supply Switches at 2MHz to Avoid AM Band DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY 16V C1 32.6k 2.2µF 10k 43.2k C1: 2.2µF , ...

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LT3581 Typical applicaTions 2MHz, 12V SEPIC Converter Can Accept Input Voltages from 9V to 16V 16V C1 3.3µF Efficiency 100 16V 12V ...

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Typical applicaTions Wide Input Range, 3.3V SEPIC Converter Can Operate from 3V to 36V V BAT 3V TO 36V (V AT START- 16V) BAT 200k D1 18V C2 10nF C1: 10µF , 50V, X7R, 1210 C2: 10nF ...

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LT3581 Typical applicaTions 1MHz, ±12V Charge Pump Topology Uses Only Single Inductor C3 1µ 1µF D1 8.2µ SW1 SW2 LT3581 SHDN GATE C1 100k 3.3µF FAULT CLKOUT SYNC SS ...

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Typical applicaTions 700kHz, 5V SEPIC Can Accept Input Voltages from 3V to 16V L1 1µF 3.3µ 16V SW1 SW2 LT3581 SHDN GATE 22µF 100k FAULT CLKOUT SYNC SS 124k ...

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LT3581 package DescripTion 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES ...

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... APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 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. ...

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... I = 2.5mA, I OUT(MAX 40V Analog/PWM, OUT(MAX 40V Analog/PWM, OUT(MAX 34V 3.2mA, I < 1µA, OUT(MAX 40V 3mA, I < 1µA, OUT(MAX 40V 3mA, I < 1µA, OUT(MAX 34V 0.9mA, I < 6µA, OUT(MAX 0310 • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2010 < 1µA, 3581f ...