LT1681ESW Linear Technology, LT1681ESW Datasheet
LT1681ESW
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LT1681ESW Summary of contents
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... The LT1681 incorporates a soft-start feature that provides a controlled increase in supplied current during start-up and after an undervoltage lockout or overvoltage/overcurrent event. The part is available in a 20-lead wide SO package to support high voltage pin-to-pin clearance. , LTC and LT are registered trademarks of Linear Technology Corporation. Q1 MURS120T3 MURS120T3 Q3 0.025 ...
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... SHDN CC V < 0.3V SHDN TG Logic High (Note 2) V < 0.3V SHDN Falling Edge Rising Edge Falling Edge Rising Edge U W INFORMATION ORDER PART NUMBER TOP VIEW 20 V LT1681ESW BST 19 TG LT1681ISW 18 BSTREF 17 BLKSENS PWRGND MAX 11 SENSE SW PACKAGE 20-LEAD PLASTIC SO = 125 C, ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 12V 0V 2V BST BSTREF VC SYMBOL PARAMETER 5V External Reference V 5V ...
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LT1681 ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 12V 0V 2V BST BSTREF VC SYMBOL PARAMETER Output Drivers V TG ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS I Boost Supply Current BST vs Temperature 5.2 5.1 5.0 4.9 4.8 0 –55 – 125 TEMPERATURE ( C) 1681 G04 5V Voltage vs Temperature REF 5.10 5.05 5.00 4.95 4.90 ...
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LT1681 W U TYPICAL PERFOR A CE CHARACTERISTICS Soft-Start Output Current vs Soft-Start Pin Voltage SOFT-START PIN VOLTAGE ( CTIO S SHDN (Pin 1): Shutdown Pin. Pin voltages ...
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CTIO S voltage on the pin is reduced to 1.5V, the pin becomes high impedance and the charging cycle repeats. The oscillator operates at twice the switching frequency of the controller. Oscillator frequency f can ...
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LT1681 CTIO S The error amplifier can also be configured as a transimpedance amplifier for use in secondary-side con- troller applications. (See Applications Information section for configuration and compensation details) SENSE (Pin 11): Current Sense ...
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W BLOCK DIAGRA LT1681 1681f 9 ...
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LT1681 U U APPLICATIO S I FOR ATIO Overview The LT1681 is a high voltage, high current synchronous regulator controller, optimized for use with dual transistor forward topologies. The IC uses a constant frequency, current mode architecture with internal logic ...
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U U APPLICATIO S I FOR ATIO Events that trigger a GFC are: a) Exceeding the current limit of the 5V b) Detecting an undervoltage condition Detecting an undervoltage condition Pulling the SHDN pin ...
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LT1681 U U APPLICATIO S I FOR ATIO translate the optocoupler information. The bandwidths of the optocoupler and amplifier should be as high as pos- sible to simplify system compensation. This high band- width operation is accomplished by using the ...
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U U APPLICATIO S I FOR ATIO to the minimum off time, the converter maximum duty cycle can be forced using the SYNC input. For example, a 30% duty cycle SYNC pulse forces 30% maximum duty cycle operation for the ...
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LT1681 U U APPLICATIO S I FOR ATIO Layout Considerations—Grounding The LT1681 is typically used in high current converter designs that involve substantial switching transients. The switch drivers on the IC are designed to drive large capacitances and, as such, ...
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U TYPICAL APPLICATIO S • • • • LT1681 1681f 15 ...
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LT1681 U TYPICAL APPLICATIO S • • • 16 1681f ...
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U TYPICAL APPLICATIO S • • • LT1681 1681f 17 ...
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LT1681 U TYPICAL APPLICATIO S LT1681/LTC1698 36V-72V V to 5V/10A Module IN (See Figure 7 for Application Schematic) LT1681/LTC1698 36V-72V V to 3.3V/20A Module IN (See Figure 9 for Application Schematic) 18 LT1681/LTC1698 Isolated 5V/10A Converter Efficiency vs Load Current ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD 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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... Intel Compatible, Wide Operating Range Controller with Internal Op Amp LTC3716 High Efficiency, 2-Phase Synchronous Step-Down Controller with 5-Bit Mobile VID No R and ThinSOT are trademarks of Linear Technology Corporation. SENSE Burst Mode is a registered trademark of Linear Technolgy Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www ...