LT4356-1 Linear Technology Corporation, LT4356-1 Datasheet
LT4356-1
Related parts for LT4356-1
LT4356-1 Summary of contents
Page 1
... N-Channel MOSFET. The output is limited to a safe value thereby allowing the loads to continue functioning. The LT4356-1 also monitors the voltage drop between the V against overcurrent faults. An internal amplifi er limits the current sense voltage to 50mV ...
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... LT4356-1 ABSOLUTE MAXIMUM RATINGS (Notes 1 and 2) , SHDN ................................................ –30V to 100V V CC SNS ............................. V – 30V or –30V FLT, EN...................................... –0.3V to 80V OUT, A OUT GATE (Note 3) .................................–0. FB, TMR, IN+ ............................................... –0. EN, FLT ..........................................................–3mA A OUT PIN CONFIGURATION TOP VIEW TMR OUT 3 13 GATE 4 SNS ...
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... All voltages are referenced to GND unless otherwise specifi ed. Note 3: An internal clamp limits the GATE pin to a minimum of 10V above the OUT pin. Driving this pin to voltages beyond the clamp may damage the device. LT4356-1 MIN TYP MAX UNITS ...
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... LT4356-1 TYPICAL PERFORMANCE CHARACTERISTICS I (Shutdown (V) CC 4356 G01 SHDN Current vs Temperature SHDN –50 – 100 TEMPERATURE (°C) 4356 G04 GATE Pull-Down Current vs Temperature 220 OVERVOLTAGE CONDITION ...
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... Overvoltage Turn-Off Time vs Temperature 500 OVERVOLTAGE CONDITION V = 1.5V FB 400 300 200 100 0 3.0 –50 – TEMPERATURE (°C) LT4356-1 Specifi cations are 12V 25° unless otherwise noted. Overvoltage TMR Current vs (V – OUT 48 OVERVOLTAGE CONDITION = 25° OUT V ...
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... V , the EN pin goes high CC impedance. SHDN (Pin 7/Pin 6): Shutdown Control Input. The LT4356-1 can be shutdown to a low current mode by pulling the SHDN pin below the shutdown threshold of 0.6V. Pull this pin above 1.7V or disconnect it and allow the internal cur- rent source to turn the part back on ...
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... 50mV – SHDN A OUT – 1.25V AUXILLARY AMPLIFIER + IN+ SNS GATE 14V CHARGE PUMP – OC OUT SHDN CONTROL LOGIC RESTART GATEOFF – 1.35V 0. TMR – + – 2μA 1.25V TMR LT4356-1 OUT – 1.25V FLT OV EN FLT GND 4356 BD 4356fb 7 ...
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... MOSFET. A higher voltage corresponds to a shorter fault timer period, ensuring the MOSFET operates within its safe operating area (SOA). The LT4356-1 senses an overcurrent condition by monitor- ing the voltage across an optional sense resistor placed between the V and SNS pins ...
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... APPLICATIONS INFORMATION The LT4356-1 can limit the voltage and current to the load circuitry during supply transients or overcurrent events. The total fault timer period should be set to ride through short overvoltage transients while not causing damage to the pass transistor. The selection of this N-channel MOSFET pass transistor is critical for this application ...
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... Transient Stress in the MOSFET crosses the 1.35V During an overvoltage event, the LT4356-1 drives a series pass MOSFET to regulate the output voltage at an acceptable level. The load circuitry may continue operating throughout this interval, but only at the expense of dissipation in the MOSFET pass device ...
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... SOA stress must also be calculated for short circuit condi- tions. Short circuit where, ΔV overcurrent timer interval. For V = 14.7V 100nF , for a prototypical calculated in the previous example. Nevertheless, to ac- LT4356 τ – – – a ...
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... Figure 8 shows the approach with a P-Channel MOSFET in place of Q2. Shutdown The LT4356-1 can be shut down to a low current mode when the voltage at the SHDN pin goes below the shutdown threshold of 0.6V. The quiescent current drops to 5μA. The SHDN pin can be pulled 30V without damaging the pin ...
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... Supply Transient Protection The LT4356-1 is 100% tested and guaranteed to be safe from damage with supply voltages up to 80V. Neverthe- less, voltage transients above 100V may cause permanent damage. During a short-circuit condition, the large change in current fl ...
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... LT4356-1 APPLICATIONS INFORMATION Design Example As a design example, take an application with the follow- ing specifi cations 14V DC with transient 80V, V ≤ 16V, current limit (I OUT LIM detection at 6V, and 1ms of overvoltage early warning (Figure 6). First, calculate the resistive divider value to limit V ...
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... TYPICAL APPLICATIONS V IN 24V D2* SMAT70A *DIODES INC. 24V Overvoltage Regulator Withstands 150V IRF640 10Ω SNS GATE OUT LT4356DE-1 7 SHDN 8 FLT 9 EN GND TMR 4356 TA05 TMR 0.1μF LT4356 OUT CLAMPED AT 32V R1 118k R2 4.99k 15 4356fb ...
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... LT4356-1 TYPICAL APPLICATIONS Overvoltage Regulator with Low Battery Detection and Output Keep Alive During Shutdown V IN 12V D2* SMAJ58A R4 402k C2 0.1μF R6 10Ω R5 105k *DIODES INC 0. SNS 10mΩ IRLR2908 R3 10Ω Q2 VN2222 SNS GATE OUT 294k ...
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... V SNS GATE OUT 13V 12 IN+ 7 SHDN R8 47k 2 LT4356DE FLT OUT GND TMR 4356 TA07 TMR 0.1μF LT4356-1 V OUT 48V 2. 140k 27k C L 300μ 4.02k R1 226k R2 4.02k PWRGD V OUT 28V R4 R6 2.5A 113k 27k C L 300μ ...
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... LT4356-1 PACKAGE DESCRIPTION 3.60 ±0.05 1.70 ±0.05 2.20 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (NOTE 6) 0.200 REF NOTE: 1. DRAWING PROPOSED VARIATION OF VERSION (WGED) IN JEDEC PACKAGE OUTLINE M0-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH ...
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... DETAIL “A” MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LT4356-1 0.497 ± 0.076 (.0196 ± .003 REF 3.00 ± 0.102 (.118 ± .004) (NOTE 4) 0.86 (.034) REF 0.1016 ± 0.0508 (.004 ± .002) ...
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... LT4356-1 TYPICAL APPLICATION Overvoltage Regulator with Linear Regulator Up to 100mA 2N2905A V IN 12V D2* SMAJ58A R6 100k *DIODES INC. RELATED PARTS PART NUMBER DESCRIPTION LT1641-1/LT1641-2 Positive High Voltage Hot Swap™ Controllers LTC1696 Overvoltage Protection Controller LTC1735 High Effi ciency Synchronous Step-Down ...