LT4356 Linear Technology Corporation, LT4356 Datasheet
LT4356
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LT4356 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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... Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: 2 Operating Temperature Range + 0.3V LT4356C-1 ............................................... 0°C to 70°C CC LT4356I-1 ............................................–40°C to 85°C + 10V LT4356H-1 .........................................–40°C to 125°C OUT Storage Temperature Range DE12 ..................................................– ...
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... OUT V = 1.25V FB Δ – 12V, LT4356I-1, LT4356C-1 SNS CC SNS CC Δ – 12V, LT4356H-1 SNS CC SNS CC Δ – 48V, LT4356I-1, LT4356C-1 SNS CC SNS CC Δ – 48V, LT4356H-1 SNS CC SNS 12V to 48V SNS CC FLT 80V A = 80V OUT 1.5V, (V – ...
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... LT4356-1 TYPICAL PERFORMANCE CHARACTERISTICS unless otherwise noted. I (Shutdown (V) CC 43561 G01 Reverse Current vs Reverse Voltage – SNS CC –15 –10 – –20 –40 –60 –80 V (V) CC 43561 G03 GATE Pull-Up Current ...
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... V – V (V) CC OUT Output Low Voltage vs Current 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 100 125 0 43561 G15 LT4356-1 Specifi cations are 12V 25° Δ GATE –1μA GATE OUT CC 0 100 125 0 ...
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... When the OUT pin volt- age reaches 0.7V away from V 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 inter- Specifi ...
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... OC OUT SHDN CONTROL LOGIC RESTART GATEOFF – 1.35V 0. TMR – + – 2μA 1.25V TMR LT4356-1 and OUT pins. CC reaches 1.25V, the FLT pin pulls low to in- TMR OUT – 1.25V FLT OV EN FLT GND 43561 BD reaches TMR 43561fd 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 for a prototypical = 100nF, P calculated in the previous example. Nevertheless, to ac- LT4356 – – – ...
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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 7μA. The SHDN pin can be pulled 60V without damaging the pin ...
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... Figure 8. Overvoltage Regulator with P-Channel MOSFET Reverse Input Protection 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 9). 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 43561 TA05 TMR 0.1μF LT4356 OUT CLAMPED AT 32V R1 118k R2 4.99k 15 43561fd ...
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... INC 0. SNS 10mΩ IRLR2908 R3 10Ω Q2 VN2222 SNS GATE OUT 294k 24.9k LT4356DE OUT 7 8 SHDN FLT 9 EN GND TMR 43561 TA03 TMR 0.1μF V OUT 12V CLAMPED AT 16V 10μF D1 ...
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... V SNS GATE OUT 13V SHDN R8 47k 2 LT4356DE FLT OUT GND TMR 43561 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 300μF ...
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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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... SNS 10mΩ IRLR2908 R3 10Ω SNS GATE OUT 0.1μF R6 10Ω LT4356DE OUT 7 8 SHDN FLT 9 EN GND TMR 43561 TA04 TMR 0.1μF COMMENTS Active Current Limiting, Supplies From 9V to 80V ThinSOT™ Package, 2.7V to 28V Output Fault Protection, 16-Pin SSOP Up to 97% Effi ...