Semiconductor Fuses

The POWR-SPEED® line of semiconductor fuses is designed for modern day sensitive power electronics devices that require superior protection against overcurrent. They offer extreme current limiting protection, balanced performance for longevity, and are available in direct bus-bar mount flush-end and blade designs to meet the needs of a global market.

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PSX Datasheet Series Details Order Samples Littelfuse PSX series 1500 V dc high-speed square body fuses are specially designed to protect batte...More Amps (A): 80, 100, 125, 160, 200, 250, 280, 315, 350, 400, 450, 500, 550, 630, 700, 800, 900, 1000, 1100, 1250 more Interrupting Rating: 250 kA @ 1500 Vdc Opening: Very Fast-Acting (FF)	PSR Flush End Datasheet Series Details Order Samples High-Speed Square Body Fuses Amps (A): 40, 50, 63, 80, 100, 125, 160, 200, 250, 280, 315, 350, 400, 450, 500, 550, 630, 700, 800, 900 more Interrupting Rating: 100 kA @ 1200 Vac, 100 kA @ 1300 Vac, 200 kA @ 600 Vac, 200 kA @ 650 Vac, 200 kA @ 700 Vac Opening: Very Fast-Acting (FF)	PSR Bolted Blade Datasheet Series Details Order Samples Littelfuse PSR Series High-Speed Square Body Fuses are specially designed for protection of power se...More Amps (A): 40, 50, 63, 80, 100, 125, 160, 200, 250, 280, 315, 350, 400, 450, 500, 550, 630, 700, 800, 900 more Interrupting Rating: 100 kA @ 1200 Vac, 100 kA @ 1300 Vac, 200 kA @ 600 Vac, 200 kA @ 650 Vac, 200 kA @ 700 Vac Opening: Very Fast-Acting (FF)
PSR DIN Blade Datasheet Series Details Order Samples Littelfuse PSR Series High-Speed Square Body Fuses are specially designed for protection of power se...More Amps (A): 40, 50, 63, 80, 100, 125, 160, 200, 250, 280, 315, 350, 400, 450, 500, 550, 630, 700, 800, 900 more Interrupting Rating: 100 kA @ 1200 Vac, 100 kA @ 1300 Vac, 200 kA @ 600 Vac, 200 kA @ 650 Vac, 200 kA @ 700 Vac Opening: Very Fast-Acting (FF)	L50QS Datasheet Series Details Order Samples The L50QS Series is a next generation High-Speed Fuse for the protection of power semiconductor devi...More Amps (A): 35, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 400, 450 more VAC (V): 500 VDC (V): 500	L70QS Datasheet Series Details Order Samples The L70QS Series is a next generation High-Speed Fuse for the protection of power semiconductor devi...More Amps (A): 35, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600 more VAC (V): 700 VDC (V): 700
L75QS Datasheet Series Details Order Samples The L75QS Series is a next generation High-Speed Fuse for the protection of power semiconductor devi...More Amps (A): 35, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600 more VDC (V): 750 Interrupting Rating: 50 kA @ 750 Vdc	L70S Datasheet Series Details Order Samples 700 Vac/650 Vdc - Traditional High-Speed Fuse Amps (A): 10, 15, 20, 25, 30, 35, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 300 more VAC (V): 700 VDC (V): 650	L50S Datasheet Series Details Order Samples 500 Vac/450Vdc - Traditional High-Speed Fuse Amps (A): 10, 12, 15, 20, 25, 30, 35, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250 more VAC (V): 500 VDC (V): 450
L15S Datasheet Series Details Order Samples Traditional Semiconductor Fuse Amps (A): 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50, 60 more VAC (V): 150 VDC (V): 100, 150	L25S Datasheet Series Details Order Samples Traditional Semiconductor Fuse Amps (A): 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80 more VAC (V): 250 VDC (V): 200, 250	L60S Datasheet Series Details Order Samples Traditional Semiconductor Fuse Amps (A): 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 17.5, 20, 25, 30, 35, 40, 45, 50, 60, 70 more VAC (V): 600 Interrupting Rating: 200 kA @ 600 Vac

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Applications
Fundamentals
Selection

A power semiconductor device is a high power electronic device that is used as a switch for control and conversion in electric power. The use of power semiconductor devices in modern power electronics is driven by the need for better power efficiency, with the ultimate goal of achieving as close to 100% power efficiency as possible. In addition to power efficiency, there is a need to make the device as small as possible, which is a driving factor as to why power semiconductors have replaced older electro-mechanical components.

Typical equipment using power semiconductor devices includes inverters, rectifiers, electric vehicle battery management systems, locomotive traction drives, industrial motor drives, factory automation systems, air conditioners, computers, telecom devices, battery chargers, and many more. To protect these very sensitive power semiconductor devices from an overcurrent fault, an extremely fast acting and low energy let-through circuit protection device is needed. The only device available in the world to protect these sensitive devices are semiconductor fuses. .

Understanding the protection requirements and selecting the right semiconductor fuse for your application can be an overwhelming, time-consuming process even for a seasoned power electronics design engineer. An important part of developing quality overcurrent protection is understanding system needs and overcurrent protective device fundamentals.

Overload Fault Condition: Defined as an overcurrent that is confined to the normal current path, which if allowed to persist in the circuit, will cause damage to equipment and/or any connected wiring. Overcurrent protective devices must disconnect circuits and equipment experiencing continuous overloads before any overheating occurs.
Short-Circuit Fault Condition: An overcurrent that flows outside its normal current path in the circuit is a short-circuit fault condition. A short-circuit fault is most commonly caused by an insulation breakdown or a faulty connection. When a short-circuit fault occurs, the current bypasses the normal load and takes a shorter path, hence the term short-circuit.

Performance capabilities of semiconductor fuses are determined in the form of various characteristic curves where two or more electrical performances are compared and represented graphically. Typical semiconductor fuse characteristic curves include:

Time Current Curve
Watt Loss Performance Curve
Temperature Derating Curve
Peak Let-through Current Curve
Arc Voltage Curve
I2t Curve

	POWR-Speed Technical Application Guide Your complete guide to high-speed (semiconductor) fuses. Download the application guide to find out more.
	POWR-SPEED^® Range of High-Speed Fuses - Flyer Optimized protection for your power electronics.
	POWR-SPEED^® Fuse Cross Reference This guide covers the most popular high-speed fuse types that Littelfuse has in stock and ready to ship.
	POWR-Speed Catalog
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	POWR-SPEED^® Catalog - Mandarin 高速半导体熔断器产品目录
	POWR-SPEED^® Fuse Cross Reference - Mandarin 本指南涵盖Littelfuse最受欢迎的高速熔断器类型，库存充足，可随时发货！交叉引用旨在对快速识别和产品选型作出指导。我们建议您在进行替换之前查看全部适用规格。
	Industrial Power Fuse Selection and Cross Reference Guide PF613