LT1640HCS8 Linear Technology, LT1640HCS8 Datasheet
LT1640HCS8
Specifications of LT1640HCS8
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LT1640HCS8 Summary of contents
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... The LT1640L is designed for modules with a low enable input and the LT1640H for modules with a high enable input. The LT1640L/LT1640H is available in 8-pin PDIP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. INRUSH CURRENT 1 ...
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... UV Low to High Transition UV High to Low Transition Low to High Transition OV High to Low Transition ORDER PART NUMBER TOP VIEW 8 V LT1640HCN8 DD LT1640HCS8 7 DRAIN LT1640HIN8 6 GATE LT1640HIS8 SENSE 5 S8 PACKAGE S8 PART MARKING 8-LEAD PLASTIC SO = 120 C/W (N8) JA 1640H = 150 C/W (S8) JA 1640HI = 0V unless otherwise noted. EE ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Power Good Threshold PG V Power Good Threshold Hysteresis PGHY I Drain Input Bias Current DRAIN V PWRGD Output Low Voltage OL PWRGD Output Low Voltage (PWRGD – ...
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LT1640L/LT1640H W U TYPICAL PERFOR A CE CHARACTERISTICS Gate Voltage vs Temperature 15.0 14.5 14.0 13.5 13.0 12.5 12.0 – 50 – 100 TEMPERATURE ( C) 1640 G04 Gate Pull-Down Current vs Temperature 55 V ...
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PIN FUNCTIONS UV (Pin 3): Analog Undervoltage Input. When UV is pulled below the 1.223V high to low threshold, an under- voltage condition is detected and the GATE pin will be immediately pulled low. The GATE pin ...
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LT1640L/LT1640H TEST CIRCUIT TIMING DIAGRAMS 2V 1.223V PHLOV GATE 1V Figure GATE Timing 50mV SENSE t PHLSENSE GATE 1V Figure 4. SENSE to GATE Timing PWRGD/PWRGD ...
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U U APPLICATIONS INFORMATION Hot Circuit Insertion When circuit boards are inserted into a live – 48V backplane, the bypass capacitors at the input of the board’s power module or switching power supply can draw huge tran- sient currents as ...
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LT1640L/LT1640H U U APPLICATIONS INFORMATION Capacitor C1 and resistor R3 prevent Q1 from momen- tarily turning on when the power pins first make contact. Without C1 and R3, capacitor C2 would pull the gate voltage ...
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U U APPLICATIONS INFORMATION Electronic Circuit Breaker The LT1640 features an electronic circuit breaker function that protects against short circuits or excessive supply currents. By placing a sense resistor between the V SENSE pin, the circuit breaker will be tripped ...
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LT1640L/LT1640H U U APPLICATIONS INFORMATION Under some conditions, a short circuit at the output can cause the input supply to dip below the UV threshold, resetting the circuit breaker immediately. The LT1640 then cycles on and off repeatedly until the ...
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U U APPLICATIONS INFORMATION Undervoltage and Overvoltage Detection The UV (Pin 3) and OV (Pin 2) pins can be used to detect undervoltage and overvoltage conditions at the power supply input. The UV and OV pins are internally connected to ...
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LT1640L/LT1640H U U APPLICATIONS INFORMATION The new threshold voltage when the input moves from low to high is • • UVH R 2 • where ...
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U U APPLICATIONS INFORMATION When the DRAIN voltage of the LT1640L is high with respect the internal pull-down transistor Q2 is off EE and the PWRGD pin high impedance state (Fig- ure 12). The ...
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LT1640L/LT1640H PACKAGE DESCRIPTION 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) +0.035 0.325 –0.015 +0.889 8.255 –0.381 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) ...
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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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... Active Current Limiting, Fast Circuit Breaker for Short-Circuit Faults www.linear.com LUCENT JW050A1 OUT 8 + SENSE 2 7 ON/OFF TRIM + 0.1 F 100 F 0.1 F – SENSE 100V 100V 100V 4 5 – – OUT CASE 3 1640 F14 LT/TP 1101 1.5K REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 100 F 16V 1640lhfb ...