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Power Semiconductors & Control ICs

A comprehensive portfolio of power semiconductor and integrated circuit technologies in industry standard and innovative packages. We design forward-thinking, application-specific solutions to provide assurance that your most demanding requirements will be met.

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    Bare Die

    Bare Die

    Industrial Fuse Blocks

    Starting with bare dies allows Littelfuse engineers to design and deliver the optimal power semiconductors for your application. Work with us to specify the size, shape, and capabilities of an ac bridge rectifier, diode module, IGBT, integrated circuit, MOSFET, Schottky diode, or thyristor module. We specialize in providing components that use silicon carbide and direct copper bonding substrates.

    Gate Drivers

    Littelfuse offers advanced gate driver ICs designed to optimize the switching performance of IGBTs, MOSFETs, and SiC-MOSFETs in power electronics. Our gate driver solutions include IGBT drivers and optically isolated gate drivers engineered for fast turnoff and high-efficiency control. Ideal for use in inverters, rectifiers, and other solid-state applications, our gate drivers ensure precise, reliable operation across demanding conditions.

    Gate Driver ICs

    Gate driver integrated circuits (ICs) control the operation of metal-oxide–semiconducotr field effect transistors (MOSFETs) and insulated gate bipolar transistor (IGBTs). Sold state design and a patented process that allows users to program the ICs’ voltage threshold make Littelfuse gate driver ICs ideal replacements for electromechanical relays and discrete diodes. We produce several versions of gate driver ICs specifically for silicon carbide MOSFETs (SiC-MOSFETs) and high-power IGBTs used in applications where fast turnoff is desirable.

    IGBT & MOSFET Driver ICs

    IGBT & MOSFET Driver ICs

    Ultrafast IGBT and MOSFET gate driver ICs ensure solid state switches perform efficiently. Littelfuse makes several integrated circuits to control gates on insulated-gate bipolar transistor and metal-oxide–semiconductor field effect transistors. We offer low side, high side, and half bridge drivers, as well as drivers optimized for automotive applications and for use with three-phase switches. Consult our gate driver brochure to learn which IC you need.

    Optically Isolated Gate Drivers

    Optically isolated gate driver ICs ensure the optimal performance of MOSFETs that perform low frequency switching tasks. As patented by Littelfuse, the integrated circuits combine and coordinate the operations of LED inputs, photodiodes, optocouplers, capacitors, and metal-oxide–semiconductor field effect transistors. This design eliminates the need for multiple discrete TRIACs, mechanical relays, and switching diodes. The result is simplified circuit design and lower component costs for solid state switches in industrial control modules and telecommunications equipment.
    • Isolated photovoltaic outputs of 5.5 V, 12 V, or 14.4 V
    • LED input current requirements for MOSFETs of 2.5 mA or 5 mA
    • Minimum short circuit currents of 1 mA or 2.5 mA
    • On and off switching speeds lower than 80 ms and 60 ms, respectively
    • Housings have UL 94 flammability ratings of V-0
    • Isolation voltage ratings of 3.75 kV
    • Certified lead-free and RoHS compliant
    • No low frequency switching limit
    • No auxiliary power supply required
    • Floating outputs facilitate use in parallel or in series
    • Galvanic input-to-output isolation
    • Compatible with reflow soldering processes
    SiCMOSFET & IGBT Driver ICs

    SiCMOSFET & IGBT Driver ICs

    SiC MOSFET and IGBT driver ICs control the operations of solid state switches. The integrated circuits Littelfuse makes for these purposes specifically drive low side switches that shunt voltage surges to ground. The drivers often pair with silicon carbide metal-oxide–semiconductor field effect transistors and insulated-gate bipolar transistors that serve on-board battery chargers, dc–dc converters, and motor controllers. One of our driver ICs is AEC-Q100-qualified for use in automobiles and EVs.
    • Available with peak voltage operating ratings from –10 V to +25 V
    • Peak operating current of 9 A
    • Output-to-sink resistance ratings of 1.5 Ω or 2.0 Ω
    • Operate in a temperature range of –40 ℃ to +125 ℃
    • 16-pin power SOIC packages with exposed thermal pads
    • Certified lead-free and RoHS compliant
    • Accept TTL and CMOS inputs
    • Split source and sink outputs allow users to tailor turn-on and turn-off timing
    • Matched rise and fall times minimize switching losses
    • Low propagation delays ensure continuous flow of current
    • Desaturation detection triggers overvoltage protection
    • Soft turn off prevents commutation failures
    • Undervoltage lockout prevents stray pulses across circuits
    • Thermal shutdown protects components from damage due to overtemperature events
    • Open drain fault detection facilitates automatic corrections by microcontrollers
    • Compatible with reflow soldering processes

    IGBTs

    Insulated-gate bipolar transistors (IGBTs) serve as current converters, solid state switches, and circuit protection devices in thousands of different applications. Littelfuse and its IXYS subsidiary meet the demand for these versatile power semiconductors by producing the largest portfolio of discrete IGBTs and IGBT modules. Whether your products require inverters, rectifiers, overvoltage protection, ESD protection, or current switching devices, we can deliver off-the-shelf or custom-built IGBTs that do the job.

    BiMOSFET

    BiMOSFET

    The BiMOSFET integrates a metal-oxide–silicon field-effect transistor (MOSFET) and an insulated gate bipolar transistor (IGBT) into a compact solid-state switch similar to an RC IGBT, featuring a monolithically integrated diode. The BiMOSFET family offers a wide range of blocking voltages (1700V to 3600V), can handle collector currents up to 75A at 110°C, and is available in various high-voltage (HV) packages, both isolated and non-isolated. Additionally, this series includes a multi-chip H-Bridge option in an SMPD package.
    • High blocking voltage up to 3600V
    • Low VCE(sat)
    • Low gate charge QG
    • High pulsed collector current
    • Monolithically integrated diode
    • Positive temperature co-efficient
    • High power densities
    • Low conduction losses
    • Low gate driver requirements
    • Reverse conduction
    • Ease of paralleling

    Capsule Type

    As a pioneer of Press-Pack IGBT technology, we are able to offer a range of class leading devices with voltage ratings of 1.7kV (900V DC link), 2.5kV (1.25kV DC link), 3.3kV (1.8kV DC link), 4.5kV (2.8kV DC link), and 6.5kV (3.6kV DC link). The construction of these devices is totally free from wire and solder bonds which all but eliminates the problems of mechanical fatigue associated with conventional modules. Internal stray inductance in both the gate connections and emitter connections is vastly reduced when compared to conventional modules leading to improved ruggedness and short circuit behavior, which is further enhanced by direct cooling of the emitter side of the chip.

    Ignition

    Ignition IGBTs turn the flow of current for electronic fuel ignition coils on and off. The insulated-gate bipolar transistors Littelfuse makes for this purpose are specifically designed for use in coil-on-plug ignition systems and can mount directly on inductive coils, The solid state switches also provide protection against electrostatic discharges and overvoltage events. This prevents vehicle fires and fuel tank explosions.
    • Available with typical blocking voltage ratings from 365 V to 410 V
    • Available with maximum current ratings from 12 A to 20 A
    • Low saturation voltages (e.g., 1.3 V, 2.07 V)
    • RoHS compliant
    • Lead-free packages available
    • Available with optional gate resistors and gate–emitter resistor
    • High pulsed current capabilities
    • Low threshold voltage for interfacing with logic circuits and microprocessors
    NPT

    NPT

    Non-punch through (NPT) IGBTs serve as solid state switches for circuits that handle high voltages. Typical applications for these insulated-gate bipolar transistors include ac and dc motor drives, power supplies, and pulse generators for lasers and x-ray machines. Littelfuse makes standard (600–1200 V), high-voltage (1600–1700), and very high-voltage (2500–4000 V) NPT IGBTs. Each has a short-circuit withstand capability of 10 µs, and our very high-voltage NPT devices can replace multiple switches, rectifiers, and discharge relays with lower voltage ratings.
    • Typical saturation voltages of 2.4–4.0 V
    • Available with a wide range of typical current ratings, from 5.5 A to 150 A
    • Square reverse bias safe operating area (RBSOA)
    • Epoxy moldings have UL 94 flammability rating of V-0
    • Voltage-controlled metal oxide-semiconductor gates
    • Positive temperature coefficients make NPT IGBTs ideal for using in parallel
    • Square RBSOA improves inductive load clamping, which allows NPT IGBTs to handle hard switching without support from snubber diodes
    • Available in several packages—TO-268, TO-247, TO-263, and proprietary ISOPLUS i4-PakTM
    • High power densities
    PT

    PT

    Punch Through (PT) IGBTs perform fast switching with low conduction losses when handling signals in the range of 100 kHz to 200 kHz. All PT insulated-gate bipolar transistors made by Littelfuse represent cost-effective alternatives to metal-oxide–semiconductor field effect transistors (MOSFETs) in lower-voltage circuits. Our GenX3TM IGBTs are optimized for use in high-power conversion applications. Consult our Power Semiconductor Product Catalog to find your best solution.
    • Rated at 600 V dc or 1.2 kV dc
    • Low voltage saturation points of 2.5 V dc to 3.4 V dc
    • Handle currents between 42 A and 120 A
    • Avalanche rated
    • Square reverse bias safety operating area (RBSOA)
    • High power density
    • Incorporation of metal oxide semiconductor (MOS) gate simplifies turn-on
    • Available in three configurations, two of which have a gate, an emitter, and a collector while the other has just a gate and an emitter
    • Three configurations allow designers to choose their best option in terms of switching frequency, efficiency, and cost
    • Available in JEDEC TO standard packages
    • Suitable for surface mounting or mounting with a single screw
    • Available with an optional antiparallel fast-recovery diode
    SMPD Packages-IGBTs

    SMPD Packages-IGBTs

    When you need dc–dc converters or ac-to-dc inverters that fit perfectly on PCBs and are sturdy enough for pick-and-place board assembly, choose Littelfuse SMPD IGBTs and BiMOSFETs. Our surface mount power devices offer low weight, high power cycling capabilities, excellent thermal performance, and isolation ratings up to 4.5 kV. Compatible with reflow soldering processes, our SMPDs come in several shapes and with differing types of silicon to serve as many requirements as possible. Common uses of these solid state switches include electric motor drives, battery chargers, and induction heaters.

    XPT

    XPT

    The highest-performing solid state switches exhibit low thermal resistance, low tail current, low energy loss, and high-speed switching capabilities. Littelfuse’s eXtreme light punch through (XPT) IGBTs deliver on all counts. Configured as either planar or trench IGBTs, these high-voltage insulated-gate bipolar transistors can be used in parallel. Doing this yields cost savings and simplifies gate drive circuit design. Installing fast-recovery diodes with our XPT IGBTs ensures smoother switching and significantly reduces electromagnetic interference.
    • Available with continuous voltage (VCES) ratings from 600 V to 4.5 kV
    • Available with typical current ratings from 9 A to 94 A
    • Saturation voltages generally below 4 V
    • Low case-to-junction resistance (e.g., 92 mK/W, 4.4 K/W)
    • Positive temperature coefficient for on-state voltage facilitates paralleling
    • Low gate current requirements
    • Available packaged with fast recovery diodes
    • International standard packages

    Integrated Circuits

    Integrated circuits (ICs) control, coordinate, and protect power supply circuits, diodes, phototransistors, shunt resistors, IGBTs, MOSFETs, and other power semiconductors. Types of ICs produced by Littelfuse include gate drivers, digital bus drivers, optocouplers, error amplifiers, high-voltage analog switches, voltage monitors, and digitally programmable capacitors. We also make ICs specifically engineered for use in telecommunications systems. Design options range from wafer fabrication and isolation barriers to multichip packaging and incorporation of overcurrent, overvoltage, overtemperature, and ESD protection.

    Digital Bus Driver ICs

    Digital Bus Driver ICs

    Innovative digital bus driver integrated circuits (ICs) produced by Littelfuse simplify the design and improve the performance of personal computers. Optical isolation of components on the chip bolstered by galvanic isolation by optocouplers eliminates the need for clocking. This reduces electromagnetic interference and radio frequency interference. Additionally, fewer capacitors mean less clutter on printed circuit boards. Uses for our digital bus driver ICs include signal monitoring and control, power over ethernet, logic-level translation, and microprocessor system interface.
    • Operate at between 2.7 V and 5.5 V
    • Available with data transmission speeds of 5 kbaud, 10 kbaud, and 500 kbaud
    • Isolation voltage of 3.75 kV
    • CSA and TTU certified
    • UL Listed
    • Surface mount and dual inline packages
    • High impedance (Hi-Z) maintained during power down, reducing voltage surges
    • Low drive current requirements
    • Galvanic input-to-output isolation
    Digitally Programmable Capacitors

    Digitally Programmable Capacitors

    Digitally programmable capacitors allow users to customize the release of stored charges to meet specific requirements for given electrical processes. For example, OCXO oscillators and capacitive sensors perform many functions. Programming a crystal or sensor’s capacitor to deliver a range of charges optimizes each function. Digitally programmable capacitors available from Littelfuse feature memory chips and wired, computer-controlled interfaces. This makes setting the capacitor simple and repeatable. Further improving their usefulness, the programmable capacitors can be used in series and incorporated into shunts.
    • Operate at between 2.5 V and 5.5 V
    • Low capacitance range, from 6.6 pF to 190 pF
    • Operate at frequencies in the range of 0 (dc) MHz to 200 MHz
    • Operate at temperatures from –40 ℃ to +105 ℃
    • Permit more than 1000 capacitance settings
    • Miniature DFN and TSOT packages available
    • Nonvolatile memory
    • Reprogrammable via two-wire leads

    Error Amplifiers

    In electrical systems, error amplifiers feed current back into a control circuit to keep the output voltage as close to the circuit’s design specification as possible. To do its job, an error amplifier must first detect the difference between the actual current and the intended output voltage. A 4-terminal 431-type shunt regulator performs this detection function in the error amplifier produced by Littelfuse. A paired Darlington transistor in our error amplifier handles the task of feeding current back into the control circuit. Common applications of the device include LED lights and dc–dc converters.
    • Operate at 1.3 V to 12.5 V over circuits’ designed temperatures
    • 350 V breakdown voltages for Darlington transistors
    • Typical accuracy of 1.299 V ± 1 %
    • 4-pin SOIC packages
    • Certified lead-free and RoHS compliant
    • Very low-profile design
    • Low power dissipation
    • Low collector current requirements
    • Highly resistant to moisture (MSL 1)
    High-Voltage Analog Switch ICs

    High-Voltage Analog Switch ICs

    High voltage analog switch integrated circuits (ICs) serve as solid state relays and current-limiting devices. They also provide overvoltage protection and enable users to lock out electronic components. The devices most often handle high-frequency switching for ultrasonic transducers, battery chargers, and automatic test equipment. Littelfuse makes two compact analog switch ICs. Our Dual-T devices combine two switches, and our Quad devices combine four switches. Both configurations employ monolithic silicon-on-insulator design to galvanically isolate the switches and allow them to operate independently.
    • Operate at 3.3 V or 5 V
    • Available with switch blocking voltage ratings of ±320 V or ±600V
    • Available with switch-on resistance ratings of 14.5 Ω, 29 Ω, and 50 Ω
    • Available with switch-to-switch isolation ratings of 60 dB at 1 kHz and 110 dB at 5 kHZ
    • Switches activated by transistor–transistor logic (TTL)
    • Include thermal shutdowns to protect against fault currents
    • Include input latches to store data
    • Available with 20 pins or 28 pins
    LED Driver ICs

    LED Driver ICs

    LED driver ICs control the brightness of LED bulbs and the stability of images on LED displays. Littelfuse makes two types of these specialized integrated circuits. While relying on different gate drivers, each delivers high efficiency with low power consumption and low unit costs. Each can also be used as a dimmer. To learn which IC provides the best solution for your application, consult out Integrated Circuits Selection Guide.
    • Operate at wide ranges of input voltage (e.g., 8 V dc to 550 V dc)
    • Employ power factor correction technology
    • Low-profile designs (e.g., 6×1.27 mm pin-to-pin)
    • Certified lead-free and RoHS compliant
    • Can be used as dimmers
    • Provide supplemental overcurrent, overvoltage, and overtemperature protection
    • 8-pin designs simplify IC design by dedicating each pin to a prescribed input or output
    • Convert at least 90% of power input to signal
    • Proven to hold brightness levels and images steady through low-level transient current and voltage surges
    Optocouplers

    Optocouplers

    Optocouplers use LEDs and phototransistors to close circuits. This ensures optical isolation of integrated circuit components, making optocouplers good choices for reducing noise. Single, dual, and linear optocouplers made by Littelfuse can be paired with shunt resistors to adjust the current required to activate the devices. We also offer solid state relay–optocoupler modules that include bridge rectifiers, Darlington transistors, and Zenner diodes. Find your solution in our Integrated Circuits Selection Guide.
    • Input-to-out isolation of 3750 Vrms
    • Available with typical current transfer ratios of 300 % to 8500 %
    • Typical input-to-output capacitance of 3 pF
    • CSA, EN/IEC, and TUV certified
    • UL Recognized
    • Available with 6 to 16 pins
    • Configured as surface mount or thru hole devices
    • Optical and on-chip galvanic isolation
    • Solid state relay–optocoupler modules allow designers to simplify circuits and reduce component counts
    • Ideal for telecommunications, industrial control, and instrumentation circuits where isolating circuitry is crucial
    Telecom ICs

    Telecom ICs

    Tip-and-ring phone lines, VOIP, and PBX systems require efficient line monitoring and switching solutions. Littelfuse delivers. Our telecom ICs include N-channel depletion metal-oxide–semiconductor field effect transistors (MOSFETs), optically isolated multipurpose chips, and line card access switches. We also offer assemblies of solid state relays, optocouplers, bridge rectifiers, Darlington transistors, and Zenner diodes. Find solutions for digital communications applications in our Integrated Circuits Selection Guide.

    Voltage-Monitoring ICs

    Voltage monitoring ICs enable many features of VOIP and IP PBX tip-and-ring telephone systems, including line-in-use detection, caller ID, and imperceptible voice recording. The integrated circuits use a high-impedance resistor divider to detect differences between the common mode voltage and other input currents. Currents with differing voltages get routed to switches while the IC creates a scaled representation of phone line voltages and outputs polarity information. The IC does this while generating virtually no noise across the circuit.
    • Operates at 3 V dc to 5 V dc
    • Common mode rejection ratio > 55 dB
    • High differential input impedance and very low common mode input impedance
    • 8-pin small outline integrated circuit
    • Fixed gain amplifier
    • Certified lead-free and RoHS compliant
    • Worldwide telephone network compatibility
    • Supports nontelephony applications such as instrumentation and industrial controls
    • Available with differential or single-ended linear output
    • Transistor–transistor and complementary metal-oxide-semiconductor (CMOS) logic-level outputs

    MOSFETs (Si/SiC)

    Littelfuse offers a comprehensive range of silicon and silicon carbide MOSFETs engineered for high-efficiency current conversion, switching, and power factor correction (PFC). Our portfolio includes discrete power MOSFETs and MOSFET modules suited for rectifiers, inverters, and PFC circuits. With a wide selection of MOSFET packages and configurations, we provide both off-the-shelf and custom-designed solutions to meet the unique needs of industrial and commercial power systems.

    Automotive Qualified

    Automotive Qualified

    Electric vehicles from passenger EVs to battery-powered forklifts require efficient solid-state switches that withstand strong vibrations and harsh operating conditions. Littelfuse meets this demand by producing automotive-qualified MOSFETs. These AEC-Q–qualified and avalanche-rated devices can serve as rectifiers and dc–dc converters in automotive electrical systems. They can also be used in audio amplifiers, motor controllers, and telecom systems. Each MOSFET boasts low on-state resistance, low gate charge, and high dv/dt ruggedness.

    Low-Power Depletion Mode

    N-channel depletion mode field effect transistors (FETs) offer highly reliable solid state relay gate solutions for automotive, industrial, and telecommunications systems. The high-voltage N-channel MOSFETs take advantage of vertical double-diffused metal-oxide–semiconductor (DMOS) architecture to deliver a small footprint. This saves PCB space without sacrificing performance. Typical applications for the devices include ignition modules, power converters, power supplies, and LED driver integrated circuits.
    • Normally closed when no power applied
    • 350 V drain-to-source voltage
    • Low cutoff voltage (VGS(off))
    • High input impedance
    • Low input and output leakage
    • Specifically designed for high-voltage applications
    • Ability to perform well in cold environments make devices good choice for automotive ignition modules
    • Small size delivers PCB space- and cost-savings
    • FET structure prevents thermal runaway and thermally induced secondary breakdown
    N-Channel Depletion Mode

    N-Channel Depletion Mode

    N-channel depletion MOSFETs offer reliable switching and current-regulating solutions for always-on circuits, such as those for emergency and burglar alarms. These metal-oxide–semiconductor field effect transistors operate as normally on solid state switches. Unlike other MOSFETs, they require no start-up voltage to open. Like other MOSFETs, they mount easily on printed circuit boards.
    • Rated at 1 kV dc
    • Normally on operation
    • Available with blocking voltages of 100 V dc to 1700 V dc
    • Low resistance while on (i.e., 1.4 Ω, 10 Ω)
    • Epoxy case with UL 94 flammability rating of V-0
    • Require zero turn-on voltage at gate terminal
    • High power densities
    • Ensure low power loss in always-on circuits
    • Easy to mount on PCBs
    N-Channel HiPerFETs

    N-Channel HiPerFETs

    N-channel HiPerFETs (TM) incorporate fast rectifiers into the architecture of a metal-oxide–semiconductor field effect transistors (MOSFETs) to deliver low reverse recovery times (trr > 250 ns). HiPerFETs made by Littelfuse also provide overvoltage protection at turnoff. This eliminates the need for discrete varistors, which simplifies the design of printed circuit boards, increases efficiency, and lowers thermal resistance. Suitable for hard switching and resonant mode operation, applications for N-channel HiPerFETs include dc–dc converters, battery chargers, and temperature and lighting controls.
    • Available with wide ranges of drain-to-source voltage ratings (e.g., 200 V dc to 1 KV dc)
    • Available with wide ranges of drain current ratings (e.g., 10 A to 100 A)
    • Avalanche rated with low total gate charge (Qg) and low intrinsic gate resistance (Rg)
    • Low inductance
    • High power densities
    • Rugged polysilicon gate cell structure
    • Available with a variety of leads and terminals
    • Easy to mount on PCBs with one screw or solder
    N-Channel Linear

    N-Channel Linear

    N-channel linear MOSFETs endure substantially higher thermal and electrical stresses than metal-oxide–semiconductor field effect transistors designed for switch mode operations. When on, the devices ensure the steady flow of current through a circuit. Linear operation produces drain-to-source voltages and drain currents high enough to cause regular MOSFETs to fail. Specially engineered linear MOSFETs suppress electro-thermal feedback and perform reliably in their current saturation ranges. Applications for N-channel linear MOSFETs include fan controllers, pulse generators, e-fuses, and current regulators.
    • Available with wide ranges of drain-to-source voltage ratings, from 75 V dc to 2.5 kV dc
    • Available with wide ranges of drain current ratings (e.g., 2 A to 62 A)
    • Guaranteed forward bias safe operating areas (FBSOAs) at 75 ℃
    • Avalanche rated with low total gate charge (Qg) and low intrinsic gate resistance (Rg)
    • Epoxy moldings with UL 94 flammability ratings of V-0
    • Designed specifically for linear operation
    • High power densities
    • Available with a variety of leads and terminals
    • Easy to mount on PCBs with one screw or solder
    N-Channel Standard

    N-Channel Standard

    Standard N-channel MOSFETs serve as highly efficient solid state switches in high-voltage systems. Designed specifically to handle hard switching, these metal-oxide–semiconductor field effect transistors also work well in resonant mode applications. Common uses for N-channel MOSFETs include dc–dc converter, electric motor controller, and pulse generator for a laser or x-ray machine.
    • Available with drain-to-source voltage ratings of 600 VDSS to 4.5 kVDSS
    • Available with an extremely wide range of on-state resistance ratings, from 9 mΩ to 625 Ω
    • Gate charge requirements as low as 7.8 nC
    • Resistive switching times generally below 50 ns
    • High power densities
    • Low gate charges allow smooth switching at high frequencies
    • JEDEC TO packages
    • Ideally suited for paralleling
    N-Channel Super Junction

    N-Channel Super Junction

    Super junction N-channel MOSFETs feature the lowest on-state resistances for solid state switches with drain-to-source voltage ratings of 600 V to 800 V. Littelfuse produces several versions of these metal-oxide–semiconductor field effect transistors. Our devices employ third- and fourth-generation fast CoolMOS* technology to ensure reliable high-speed switching for power supplies, dc–dc converters, and induction heaters. We also make multichip super junction N-channel MOSFETs configured for use as buck converters, totem pole devices, or dc choppers.CoolMOS* is a trademark of Infineon Technologies AG.
    • Available with drain-to-source voltage ratings of 600 VDSS and 800 VDSS
    • Ultra-low on-state resistance ratings (e.g., 7 mΩ, 45 mΩ, 125 mΩ
    • Typical drain current (ID25) between 25 A and 47 A
    • Gate charge requirements below 250 nC
    • Avalanche rated
    • High power densities
    • Available with Schottky diodes, ultra-fast antiparallel diodes, or fast recovery diodes
    • Direct copper bond substrate isolation reduces thermal resistance from junction to heat sink
    • International standard packages

    N-Channel Trench Gate

    Trench gate N-channel MOSFETs boast ultra-low on-state resistance and excellent temperature tolerance. These characteristics make them ideal solid state switches in low-voltage, high current systems and harsh environments. Suitably, principal applications for these metal-oxide–semiconductor field effect transistors include light EVs, unmanned aerial vehicles, and onboard battery chargers. Most of the trench gate N-channel MOSFETs made by Littelfuse incorporate HiPerFETTM technology. This addition boosts switching speeds while reducing or eliminating the need for parallel switches.
    • Available with drain-to-source voltage ratings of 40 VDSS to 300 VDSS
    • Extremely low on-state resistance ratings (e.g., 0.85 mΩ, 1.3 mΩ, 3.1 mΩ)
    • Available with a wide range of typical drain currents (ID25) from 32 A and 660 A
    • Operate at temperatures from –40 ℃ to 175 ℃
    • Avalanche rated
    • High power densities
    • Low on-state resistance minimizes power losses
    • Optimized for synchronous rectification in switched mode power conversion applications
    • International standard packages
    N-Channel Ultra Junction

    N-Channel Ultra Junction

    Ultra junction N-channel MOSFETs boast the lowest on-state resistances of any metal-oxide–semiconductor field effect transistors. The solid state switches also offer increased efficiency, a reduced need for snubber diodes, and lower risks for commutation failures by incorporating fast recovery diodes. Optimized for high-speed and hard switching, applications for ultra junction N-channel MOSFETs include dc–dc converters, electric forklifts, motor drives, onboard battery chargers, power factor correction circuits, and telecommunications equipment.
    • Available with with a wide range of drain-to-source voltage ratings of 135 VDSS to 1 kVDSS
    • Ultra-low on-state resistance ratings (e.g., 2.5 mΩ to 21 mΩ)
    • Available with an extremely wide range of typical drain current (ID25) ratings, from 2 A to 200 A
    • Gate charge requirements as low as 7 nC
    • High power densities
    • Low gate charges ensure higher efficiency while handling lower current loads
    • Soft recovery reduces electromagnetic interference
    • Suitable for paralleling
    • International standard packages with low inductance
    P-Channel

    P-Channel

    P-channel MOSFETs make ideal solid-state switches for stepping down voltage or connecting loads to ground. In the language of circuit designers, these metal-oxide–semiconductor field effect transistors make good buck converters and high side switches. P-channel MOSFETs can also be paired with N-channel MOSFETs to ensure complete handling of positively charged holes and negatively charged electrons for applications that require totem pole outputs. Littelfuse P-channel MOSFETs include PolarTM devices with very low on-state resistance and trench gate devices well-suited for automotive applications.
    • Available with drain-to-source voltage ratings of –50 VDSS to –600 VDSS
    • Available with 0n-state resistance of 8 m Ω to 1.2 Ω
    • Available with gate charge requirements of 39 nC to 740 nC
    • Avalanche-rated
    • High power densities
    • Low on-state resistances with positive temperature coefficients make P-channel MOSFETs easy to parallel
    • Low gate charges simplify driver requirements
    • JEDEC TO standard packages
    • Available in bolt-down and surface mount configurations

    Silicon Carbide-Multichip Configurations

    Using multichip SiC MOSFETs allows PCB and integrated circuit designers to reduce component counts while also increasing current density. Littelfuse subsidiary IXYS produces several versions of these discrete MOSFETs in four configurations—common cathode, parallel cathode, phase leg, and phase leg with Schottky diodes. Each of our multichip SiC MOSFETs achieves higher switching speeds and lower switching losses than equivalently rated silicon MOSFETs. Common applications for these solid state switches include dc–dc converters, industrial motor drives, solar inverters, battery chargers, and switch mode power supplies.

    SMPD Packages-MOSFETs

    SMPD Packages-MOSFETs

    Choose Littelfuse SMPD MOSFETs for applications requiring ultra-compact and lightweight dc–dc converters and inverters that save space on printed circuit boards. We provide these surface mount power devices in single-phase, three-phase, boost, buck, full bridge, and half bridge configurations. Each delivers multiple benefits, including an ability to share heat sinks with other devices and a capability to withstand high vibrations. These features make SMPD MOSFETs good solid state switches for battery chargers and motor controllers in appliances and portable electronics.

    Switchable Current Regulators

    Switchable Current Regulators

    Switchable current regulators control the flow of voltage to startup circuits. The specialized three-pin metal-oxide–semiconductor field effect transistors (MOSFETs) also support surge protective devices and resettable fuses in communications and networking equipment that rely on switched-mode power supplies. Since MOSFETs perform multiple functions, using switchable current regulators allows circuit and printed circuit board designers to eliminate discrete resistors and diodes.
    • Rated at 450 V ac or 900 V ac
    • Continuous power dissipation of 40 W
    • High dynamic resistance ratings of 58 kΩ or 9–900 kΩ
    • Meet JEDEC TO-220 and TO-252 standards for pin spacing
    • Operate in analog and mixed-signal systems
    • Replace multiple resistors and diodes
    • Allow PCB designers to reduce the number of discrete devices and simplify circuits
    • Available with option to let users program resistor current source

    Power Diodes

    Diodes for power supply applications require low reverse recovery times and low forward voltage drops. Each discrete diode produced by Littelfuse boasts these characteristics, as well as low leakage. Our rectifier, ultrafast rectifier, fast recovery, and silicon Schottky diodes offer optimal switching solutions for dc–dc converters, induction heaters, and ultrasonic cleaners and welders. The Schottky devices are especially suited for use in EVs. Consult our Power Semiconductor Product Catalog to find the diode you require.

    Avalanche

    Avalanche

    Avalanche-rated rectifier diodes, or avalanche diodes, offer flexible solutions for applications that require converting alternating current to direct current. Littelfuse subsidiary IXYS makes a large variety of avalanche diodes optimized for use in systems that operate at frequencies in the range of 50–60 Hz. Each of these solid state switches mounts easily on a printed circuit board. Depending on their configurations avalanche-rated rectifier diodes can also serve as single- and three-phase bridges.
    • Available with maximum repetitive reverse voltage (VRRM) ratings of 800 V to 1.6 kV
    • Available with average forward current IFAVG ratings of 2.3 A to 110 A
    • Planar glass passivated chips
    • RoHS compliant
    • Available in single, phase leg, common cathode, and dual diode configurations
    • International standard packages
    • Low current leakage
    Breakover Diodes

    Breakover Diodes

    Breakover diodes (BODs) serve as solid state switches and surge protective devices. BODs work by shunting a percentage of current and blocking transient voltages above the rating of the main circuit. Designers often use BODs to provide overvoltage, lightning, and arc-flash protection to thyristors and batteries. The power semiconductors can also be used as trigger devices for lasers and to pulse current to energy discharge circuits.
    • Available with a wide range of breakover ratings, from 400 VBO to 4.2 kVBO
    • Available with voltage tolerances of ±50 V or ±100 V
    • Handle pulse currents up to 200 A
    • Low forward current (Ifavm), from 0.2 A to 1.25 A
    • Very low temperature dependence (e.g., 0.7 • 10–3 K, 2 • 10–3 K)
    • Epoxy moldings with UL 94 flammability rating of V-0
    • RoHS compliant
    • Fast or very fast turn-on
    • Available in oilproof packages
    • Low weight
    • Designed with pins to facilitate soldering on printed circuit boards
    Fast Recovery

    Fast Recovery

    Fast recovery diodes work by themselves and with thyristors as solid state switches and snubber devices. The diodes’ low reverse recovery times facilitate high speed switching. Fast recovery also protects insulated-gate bipolar transistors (IGBTs) and integrate gate-commutated thyristors (IGCTs) against commutation failures. Through our IXYS subsidiary, Littelfuse offers several kinds of fast recovery diodes with a wide variety of performance characteristics.. Identify your best solution in our Power Semiconductor Product Catalog.
    • Available with typical reverse recovery times as low as 0.3 µs
    • Available with maximum repetitive recovery voltage (Vrrm) from 200 V to 6 kV
    • Available with low maximum forward voltage drop ratings of 900 mV to 4.33 V
    • Available with a broad range of average forward current (Ifav) current ratings of 5 A to 2.423 kA
    • Available in single, dual, and common cathode configurations
    • Low current leakage
    • Low terminal-to-junction thermal resistance
    • International standard packages for all but select HiPerDYN diodes designed for superior voltage isolation
    Rectifier

    Rectifier

    Rectifier diodes convert alternating current to direct current. You find the solid state switches in almost all electrical systems. For this reason, Littelfuse produces many types of low- and high-current rectifiers with a range of designs and performance characteristics. Consult our Power Semiconductor Product Catalog to decide if a D-Pak, Teccor®, capsule-type, easy mount, or stud-type rectifier best serves your application.
    • Available with a wide range of voltage ratings, from 200 Vrpm to 7.2 Vrpm
    • Available with a wide range of current ratings, from 15 A to 12.1 kA
    • Operate in a temperature range of –40 ℃ to 150 ℃
    • RoHS compliant
    • Available in international standard packages
    • Available in surface mount, capsule, and stud configurations
    • Optimized to produce low conduction losses
    • High surge current capabilities

    Schottky (Si/SiC)

    Silicon Schottky diode rectifiers produce very low forward voltage drops while serving as ac switches in power converts and switched-mode power supplies. The devices can also be used to control the flow of current to other protection diodes. Littelfuse makes almost 100 types of silicon Schottky diodes. Consult our Power Semiconductor Product Catalog to find the best solution for your application.
    • Available with wide ranges of current ratings (e.g., 5 A and 200 V ac, 30 A and 100 V ac)
    • Low to ultra-low forward voltage drop (e.g., 0.80 V ac at 10 A, 0.68 V ac at 20 A)
    • Operate at up to 150 ℃
    • Meet ITO-220AB standards for pin spacing
    • Low current leakage
    • Common cathode configuration
    • Single-screw mounting design
    • Guard rings enhance ruggedness and long-term reliability
    Semifast

    Semifast

    SemiFast diodes offer ultra-low reverse recovery times, low power usage, and negligible forward current losses in applications requiring solid state switches. The antiparallel diodes produce minimal noise and little heating while reliably performing high-frequency switching operations. Used as discrete devices or as components of integrated circuits, SemiFast diodes can serve as antisaturation diodes, snubber diodes, freewheeling diodes in power converters and motor controls, and rectifiers in switched-mode power supplies.
    • Rated at 1400 Vrms, 1600 Vrms, and 1800 Vrms
    • Typical reverse recovery time (trr) of 40 ns
    • Average forward current (Ifavm) of 63 A
    • Planar passivated junctions
    • Epoxy moldings with a UL 94 flammability ratings of V-0
    • JEDEC TO-247AD package sizes
    • Soft recovery
    • Extremely low switching losses
    • Low voltage peaks reduce need for surge protection devices in circuit
    • Operate at lower temperatures, which saves board space and simplifies circuit design by reducing need for cooling

    Power Modules

    Diode modules and thyristor modules for power control applications perform best when they possess low thermal impedance and high overload capacity. Each of the modules produced by Littelfuse meet those requirements while also exhibiting low current leakage and low forward voltage drop. Designed for easy bolt-down mounting, our diode and thyristor modules offer full pressure contact to ensure high efficiency. Manufactures typically install the modules as rectifiers, ac–dc converters, and ac switches in induction heaters, electric motors, and lighting controls.

    AC Bridge Rectifiers

    Ac bridge rectifiers convert alternating current from mains to direct current for electric motors and other types of equipment. Littelfuse subsidiary IXYS makes several single-phase and three-phase ac bridge rectifiers that coordinate the operations of diodes, thyristors, and MOSFETs across integrated circuits. The solid state ac–dc switches boast small footprints, and different configurations can perform half- or full-bridging. Consult our Integrated Circuits Selection Guide to identify solutions for your application.

    High-Voltage Rectifiers

    High-Voltage Rectifiers

    High voltage rectifiers convert alternating current to direct current along circuits carrying up to 24 kV. These solid state switches make good choices for applications such as electron beam welders, lasers, and x-ray equipment that require power cycling and generating pulses. Littelfuse subsidiary IXYS offers single-phase and three-phase high voltage rectifiers. Each ac–dc converter provides an economical solution for producing controlled dc power from one or three mains.
    • Available with maximum repetitive reverse voltage (Vrrm) ratings of 3.2 kV to 24 kV
    • Available with average forward current Ifavg ratings of 1 A to 23 A
    • Available with total circuit resistance (rt) ratings from 16 mΩ to 1.8 Ω
    • Avalanche rated
    • Hermetically sealed epoxy housings prevent contamination from dust and corrosion from moisture
    • Sealed housings allow use in oil for cooling with or without a plate
    • Can be used in series and in parallel
    • High voltage capabilities reduce need for protective devices and protection circuits
    • Mount with single bolt
    • International standard packages

    Single-Phase Bridges – AC Bridge Rectifiers

    Single-phase bridges use diodes to convert alternating current to direct current for electric motors, power supplies, and battery backups. Littelfuse makes these rectifiers for single-phase electrical systems with a wide range of voltage and current ratings, as well as in several different types of packages. Each of our single-phase bridges employs the most up-to-date technology to offer enhanced temperature and power cycling.
    • Maximum repetitive reverse blocking voltage (Vrrm) ratings from 800 V to 1.8 kV
    • Bridge output currents (Idav) at 100 ℃ from 14 A to 124 A
    • Maximum forward surge current (I) from at 45 ℃ from 120 A to 1.8 kA
    • Isolation voltages up to 3 kV
    • Planar passivated chips
    • Epoxy housings with UL 94 flammability ratings of V-0
    • RoHS compliant
    • International standard packages
    • Soldering pins for PCB mounting
    • Small size delivers space and weight savings
    Three-Phase Bridges - AC Bridge Rectifiers

    Three-Phase Bridges – AC Bridge Rectifiers

    Littelfuse subsidiary IXYS makes three types of MOSFET modules that serve as bridge rectifiers and power factor correction circuits. Each module consists of a metal-oxide–semiconductor field effect transistor and a fast recovery diode. One of the modules also includes an IGBT with non-punch through architecture that ensures a large reverse bias safety operating area (RBSOA). The modules frequently get used as solid state ac switches and ac–dc converters in welding machines, switched-mode power supplies, and uninterruptible power supplies.
    • Drain source (Vdss) and continuous collector-to-emitter voltage (Vces) ratings depend on architecture and diode bridge pairings
    • Available with typical current ratings from 35 A to 130 A
    • Available with net power (Pn) ratings of 10kW, 15 kW, or 30 kW
    • Isolation voltage ratings of 3.6 kVrms
    • Kelvin source terminals mean devices require low drive currents
    • Low package inductance enables high-speed switching
    • Direct copper bond ceramic base plates optimize heat transfer characteristics
    • Solderable pins facilitate mounting on printed circuit boards
    • Compatible with wave soldering
    • Can also mount with two screws
    • International standard packages

    Solid State Relays

    OptoMOS® solid-state relays enable fast, reliable, and bounce-free current switching electrical systems using alternating current and carrying high loads. Littelfuse offers these semiconductor-based relays in compact designs suitable for mounting on printed circuit boards and requiring minimal heat sinking. Our solid-state relays make ideal replacements for reed relays and electromechanical relays.

    OptoMOS Relays

    OptoMOS® relays come in three configurations. The solid state relays have normally open (Form-A), normally closed (Form-B), or switchover (Form-C) switches. Each relay is an integrated circuit consisting of semiconductors, and most can mount on printed circuit boards. The devices make good alternatives to reed relays and other types of electromechanical relays because they require less power to operate. Consult the Littelfuse Integrated Circuits Selection Guide to identify the best relay for your application.

    Combination NO+NC

    Combination normally open and normally closed OptoMOS® relays provide flexible current switching solutions for telecommunications, industrial, security, metering, and medical applications. The semiconductor assemblies include Form-A and Form-B poles that open or close circuits depending on input voltages. Since the devices contain no moving parts, they are smaller, more efficient, and less susceptible to failure than are reed relays or other types of electromechanical relays.
    • Available with blocking voltages of 60 V, 250 V, and 350 V
    • Available with typical load currents from 120 mA to 1 A
    • Available with on-state resistance ratings of 400 mΩ to 35 Ω
    • Available with isolation voltages up to 3.75 kV
    • Plastic housings have UL flammability ratings of V-0
    • CSA and TUV certified
    • UL recognized
    • Low current leakage
    • Generate no electromagnetic or radio frequency interference
    • Low drive current requirements
    • Galvanic input-to-output isolation
    • Available with current-limiting circuitry
    • Surface mount configurations available
    Normally Closed Relays

    Normally Closed Relays

    Normally closed OptoMOS® solid-state relays make highly efficient and reliable options for ensuring the continuous flow of direct current. Unlike electromechanical relays, these semiconductor assemblies contain no moving parts. This prevents fatigue and failure while also providing space and weight savings. Littelfuse makes one-pole, dual-pole, voltage-controlled, and dc-only normally closed relays. You will find our OptoMOS® relays in data acquisition devices, industrial control modules, medical equipment, meters, and security systems.
    • Available with blocking voltage ratings from 30 V to 800 V
    • Available with load current ratings from 75 mA to 3.25 A
    • Available with a broad range of on-state resistance ratings, from 300 mΩ to 50 Ω
    • Isolation voltage ratings up to 5 kV
    • Housings have UL 94 flammability ratings of V-0
    • Output capacitance lower than 1 nF
    • Certified lead-free and RoHS compliant
    • Available with unidirectional or bidirectional polarity
    • Configured with 4, 6, or 8 pins
    • Generate no electromagnetic or radio frequency interference
    • Low drive current requirements
    • Optically isolated outputs and galvanic isolation from input to output
    Normally Open Relays

    Normally Open Relays

    Normally open OptoMOS® solid-state relays make highly efficient and reliable options for keeping circuits open. Unlike electromechanical relays, these semiconductor assemblies contain no moving parts. This prevents fatigue and failure while also providing space and weight savings. Littelfuse makes one-pole, dual-pole, voltage-controlled, and dc-only normally open relays. We also offer relays with two MOSFETs and relays with built-in protection against voltage surges. You will find our OptoMOS ®relays in data acquisition devices, industrial control modules, medical equipment, meters, and security systems.
    • Available with blocking voltage ratings from 30 V to 1 kV
    • Available with load current ratings from 50 mA to 1 A
    • Available with a very broad range of on-state resistance ratings, from 40 mΩ to 35 Ω
    • Isolation voltage ratings up to 3.75 kV
    • Housings have UL 94 flammability ratings of V-0
    • Output capacitance ratings lower than 50 pF
    • Certified lead-free and RoHS compliant
    • Available with unidirectional or bidirectional polarity
    • Configured with 4, 6, or 8 pins
    • Generate no electromagnetic or radio frequency interference
    • Low drive current requirements
    • Optically isolated inputs and galvanic isolation from input to output
    OptoMOS Power Relays

    OptoMOS Power Relays

    OptoMOS® power relays serve as highly reliable dc switches in electric motors, flow meters, medical equipment, robotics, and vehicles. The integrated circuits made by Littelfuse subsidiary IXYS consist of LED-controlled semiconductors and MOSFETs. Using the normally open (Form-A) relays with heat sinks boosts load current handling capabilities. Consult the Littelfuse Integrated Circuits Selection Guide to identify the best relay for your application.
    • Blocking voltage (Vp) ratings from 60 V to 1 kV
    • Available with a wide range of load current ratings in free air, from 650 mA to 9 A
    • Available with a higher range of load current ratings when used with heat sinks, from 1.6 A to 22.8 A
    • Available with very low and low on-state resistance ratings, from 50 mΩ to 3 Ω
    • 2.5 kVrms isolation voltage
    • UL-recognized
    • Devices with unidirectional and bidirectional outputs available
    • Low drive current requirements
    • Use of direct copper bond ceramic substrates delivers low thermal impedance
    • Generate no electromagnetic or radiofrequency interference
    • Galvanic input-to-output isolation
    • International standard 4-pin and 8-pin designs

    Stacks, Subsystems & Assemblies

    Power semiconductor stacks and subsystems combine and coordinate solid state switches, diodes, thyristors, IGBTs, and transient voltage surge suppressors in compact, easy-to-install assemblies. The stacks most often serve as rectifiers and inverters. Each off-the-shelf stack made by Littelfuse includes a low-noise cooling fan and high-speed fuses to protect against short circuits. We also supply accessories for power semiconductor stacks and subsystems, including clips, clamps, mounting grease, and heat sinks. Contact us to discuss custom designing a stack if you do not find a prebuilt solution that meets your needs.

    Clamps

    Using bar clamps specifically designed for high-power IGBT modules ensures the insulated-gate bipolar transistors remain in place and work reliably. Littelfuse makes a wide variety of such clamps for all sizes of capsule-type IGBT modules. Insulation on the clamps prevents heat damage, and the clamps themselves prevent semiconductors and diodes from shifting due to vibration or movement.
    • Available with capsule holding forces from 450 kgf to 8500 kgf
    • Available with mounting surface diameters from 19 mm to 132 mm
    • Available with rod sizes from M6 to M16
    • Ideal for capsules with diameters of 126 mm
    • Precalibrated indicators eliminate the need for special tools or torque wrenches
    • Two-rod system ensures even clamping force
    • Junctions withstand temperatures up to 190 °C
    Cooler Accessories

    Cooler Accessories

    Connect coolers for semiconductor power stacks to water supplies with these stainless steel nozzles and plastic hoses. Each M12 hose nozzle is threaded to ensure a secure connection. Hoses come in 10 mm or 12 mm lengths.

    Coolers

    Coolers

    Semiconductor power stacks require external cooling to prevent component failures due to overheating. Littelfuse makes several coolers that use water to ensure IGBTs, MOSFETs, fuses and other devices in power stacks remain within their nominal operating temperatures. Each cooler is designed to clamp securely against a capsule-type or rectangular power stack without damaging the semiconductor assembly. Each cooler is also designed to keep water flowing continuously while a power stack operates.
    • Available with cooler thicknesses of 16 mm to 34 mm
    • Available with bus bar thicknesses of 6.4 mm to 10 mm
    • Net weight per cooler ranges from 400 g to 5.95 kg
    • Quarter-inch BSPP (British Standard Parallel Pipe) hydraulic fittings
    • Made from aluminum or copper
    • Very flat (20 µm) and very smooth (0.8 µm) contact areas
    • Designed for use in tandem and performance-tested with two or three coolers cooling a single semiconductor assembly
    • International standard packages

    Heat Sinks

    Aluminum heat sinks offer contact and air cooling for semiconductor power stacks. Littelfuse makes three off-the-shelf heat sinks specifically designed to clamp against power stacks. We produce flat base, finned, and raised platform heat sinks to accommodate multiple applications.
    • Available with areas from 2.979 m3 to 11.172 m3
    • Available with peripheral measurements of 1.059 m to 6.620 m
    • Available with weights from 8.1 kg to 30 kg
    • Flat, smooth surfaces ensure secure clamping and protect power stack housings
    • International standard packages

    Power Semiconductor Accessories

    Ensuring power semiconductor stacks perform optimally requires installing and maintaining the assemblies with high-quality components. For this reason, Littelfuse offers several types of capsule insulators, silicon sleeve cables, and coaxial cables. Each cable comes with color-coded red and white terminals. We can also deliver mounting grease for press-pack IGBTs and PTFE tubing for supplying water to external coolers.

    Power Stacks

    High power stacks from Littelfuse combine and coordinate the operations of diodes, IGBTs, surge protective devices, and fuses. Each sealed and fan- or water-cooled semiconductor assembly contains at least two diodes and two insulated-gate bipolar transistors. Depending on their components and configurations, our power stacks can serve as single-phase, three-phase, or six-phase bridge rectifiers. Customers can choose the types of overvoltage, overcurrent, and short-circuit protection they require. Contact us to discuss fully custom-built solutions.
    • Link voltage of 2.8 kV dc
    • Current rating of 1.2 kArms
    • UL Recognized
    • RoHS compliant
    • Integrated snubber circuit
    • Advanced optically fired gate trigger units
    • Complete pressure contact construction
    • Short inductance paths reduce inductance peaks
    • Short paths between components reduce inductance peaks
    • Preloaded clamping evenly distributes applied forces

    Thyristors (SCR & TRIAC)

    Littelfuse offers a wide range of discrete thyristors designed for reliable switching and overvoltage protection in demanding electronic systems. Our portfolio includes power SCR (silicon-controlled rectifier) thyristors for unidirectional control, TRIACs for bidirectional switching, and integrated QUADRACs combining TRIACs and DIACs for enhanced alternating current performance. We also supply standalone DIACs for precise thyristor gate triggering. Common TRIAC applications and power SCR uses include motor speed regulation, lighting control, and heating systems.

    AC Switches

    High-current electrical systems such as those for tankless water heaters depend on solid state ac switches. Littelfuse offers a specialized thyristor module for those types of applications. Our 90 A ac controller module contains silicon controlled rectifier (SCR) thyristors. It operates at frequencies of 50 Hz to 60 Hz and has glass passivated (nonreactive) contacts to reduce energy loss due to metal–silicon contact.
    • Typical current (ITrms rating of 90 A
    • Voltage (VDRM) rating of 60 V
    • Surge capability up to 950 A
    • Handles frequencies in the range of 50 Hz to 60 Hz
    • UL Recognized
    • RoHS compliant
    • Very low turn-on and turnoff times
    • Low gate current requirements
    • Glass passivated junctions ensure low junction-to-case thermal resistance
    • SOT-227B package with minimum isolation voltage of 2.5 kV
    Fast Thyristors

    Fast Thyristors

    Use fast thyristors in high-voltage electrical systems that require high-speed, low-loss signal switching. Littelfuse produces these types of power semiconductors in several configurations, but all can serve as inverters. Other applications for the solid state switches include uninterruptible power supplies and pulse generators. Our asymmetrical fast thyristor minimizes voltage loss during device turnoff.
    • Maximum turnoff times below 35 µs
    • Available with dynamic resistance voltage (VDRM) ratings from 294 V to 2.5 kV
    • Available with maximum repetitive reverse voltage (VRRM) ratings from 10 V to 2 kV
    • Available with average on-state current (ITAV at 55 ℃) ratings of 128 A to 1.11 kA
    • Low resistance ratings (e.g., 212 m Ω, 2.1 Ω)
    • Available in capsule and stud configurations
    • Low gate current requirements
    • Operate in wide range of ambient temperatures, from –40 ℃ to +125 ℃
    • International standard packages

    Gate Turn Off

    Variable-speed ac industrial motors, inverters, and traction motors rely on gate turn off (GTO) thyristors. When engaged, the devices block current. Users can switch GTO thyristors on manually, and the devices can be configured to allow current to flow symmetrically (i.e., in both directions) or asymmetrically (i.e., in one direction). Although insulated gate bipolar thyristors (IGBTs) and integrated gate-commutated thyristors (IGCTs) have replaced GTO thyristors in many applications, Littelfuse remains committed to producing and improving GTO thyristors as the devices of choice for high-current circuit control.
    • Available with dynamic resistance voltage (VDRM) ratings from 1.2 kV to 4.5 kV
    • Available with maximum repetitive reverse voltage (VRRM) ratings from 400 V to 2 kV
    • Available with peak turnoff current (ITGQ) ratings from 400 A to 4 kA
    • On-state voltage drops below 4.4 V
    • Maximum turnoff times below 30 µs
    • Capsule and stud configurations available
    • Low gate trigger current requirements
    • High current surge capabilities
    • International standard packages

    Medium Voltage

    Phase control medium voltage thyristors optimize direct current switching in electrical systems carrying voltages up to 6.5 kV and currents below 4 kA. These specially designed solid state switches limit conduction losses as voltage increases. Medium voltage thyristors also ensure turnoff times do not increase in line with increases in voltage. By doing that, the thyristors lower risks for commutation failures. Littelfuse medium voltage thyristors perform best when used in series. Applications for the solid state switches include dc–dc converters, DC motor drives, and volt–amp (VAR) compensators.
    • Rated at between 3.2 kA and 6.5 kA
    • Available with silicon capsule diameters from 35 mm to 96 mm
    • Optimized for series operation in electrical systems with voltage ratings up to 6.5 kV and current ratings less than 4 kA
    • Maximum power handling capacity achieved at line frequencies below 400 Hz
    • Patented distributed gate architecture ensures excellent switching performance over wide ranges of voltages and currents
    • Engineered to achieve optimal balance between conduction losses, turnoff time, and power-handling capacity
    • Can be used in parallel
    • Predictable fast turnoff prevents commutation failure

    Phase Control

    Phase control thyristors control the flow of current through circuits. The gates of the solid state switches open in line with the sine wave of electrical currents. Littelfuse makes two types of these power semiconductors for high-power applications. You will find our capsule-type and stud-type phase control thyristors in industrial dc motor drives, marine and rail propulsion systems, wind power converters, and electrochemical power supplies.
    • Operate at voltages from 400 Vrms to 6.5 kVrms
    • Available with nonrepetitive surge current (ITSM) ratings up to 8 kA
    • Typical gate turn-on time of 1 µs to 3 µs
    • Low resistance ratings of 0.171 mΩ to 1.79 mΩ
    • Operate at temperatures from –40 ℃ to +125 ℃
    • Low conduction losses
    • Optimized for applications with line frequencies up to 400 Hz
    • Maximum current ratings for thyristors this size
    • Lowest thermal resistance of thyristors this size

    QUADRAC

    A QUADRAC is a thyristor assembly that handles ac switching. Especially suited to serving as dimmer switches for LED bulbs, QUADRACs combine bidirectional TRIACs (triodes for alternating current) with DIACs (diodes for alternating current). Putting the solid state switches in a single device enhances a circuit’s noise immunity, improves efficiency, and simplifies circuit design.
    • Available with 400 Vdrm/Vrrm and 600drm/Vrrm
    • Minimum of 2.5 kVrms ac isolation between mounting tab and active terminals
    • Typical forward current ratings (It(rms)) of 8 A, 12 A, and 4–15 A
    • Surge capabilities of 200 A to 600 A
    • UL Recognized
    • RoHS compliant
    • Available in alternistor versions that eliminate the need for snubber diodes
    • Available in TO-220 and TO-220AB packages
    • Provide full control of light output at extreme low end of current loads
    • Reduced need for heat sinking
    • Reliable dimming enhances useful lifespans of LEDs
    SCR

    SCR

    Littelfuse silicon-controlled rectifiers (SCR) and SCR modules for efficient switching offer a broad range of silicon-controlled rectifier solutions designed for precise, efficient switching in low-current circuits. Our SCR devices activate with minimal gate current and feature fast turn-off capabilities, reducing the risk of commutation failure. Common applications include strobe lights, fluid level sensors, and capacitive-discharge ignition systems. We also manufacture SCR modules and discrete SCRs optimized for solenoids in ground fault circuit interrupters (GFCIs) and other demanding electronic controls.
    • Blocking voltage ratings of 200 V dc to 600 V dc
    • Available with surge capabilities of 15 A, 25 A, and 30 A
    • Available with ampere ratings of 1 A, 1.5 A, and 2 A
    • Turnoff times below 55 µs
    • RoHS compliant
    • Available in surface mount and axial pass thru configurations
    • Glass passivated junctions ensure durability
    • Sensitive gates allow for direct interfacing with microprocessors
    • Compatible with lead-free reflow soldering processes
    SIDAC

    SIDAC

    SIDACs, or more properly, silicon diodes for alternating current, primarily serve as pulse current ignition switches in metal halide lamps and xenon lights. The ac switches operate in a normally on manner, allowing low-voltage current to flow continuously. As a SIDAC heats during each cycle, the power thyristor generates a pulse that keeps gas in the lamp or bulb burning.
    • Triggering voltages of 190 V ac to 380 V ac
    • Low on-state voltages of 1 V ac to 15 V ac
    • Typical on-state current of 1 A
    • Glass passivated junctions
    • RoHS compliant
    • Available in surface mount and axial leaded configurations
    • Available with unidirectional or bidirectional performance
    • Produce multiple pulses in each half cycle at 50–60 Hz
    • Blocking capability ensured by glass passivated junctions
    • Also used in high-voltage power supplies and natural gas igniters
    TRIAC

    TRIAC

    Properly named triodes for alternating current, TRIACs act as thyristors. They serve as solid state switches in heaters, lighting controls, and motor drives for power tools and home appliances. Three versions of the ac switches exist. Sensitive TRIACs open and close low-voltage digital control circuits. Standard TRIACs ensure the continuous flow of alternating current. Alternistor TRIACs handle high-speed switching tasks that produce large inductive loads. Each TRIAC produced by Littelfuse comes in sensitive, standard, and alternistor versions. All are designed for mounting on the surface of printed circuit boards.
    • High voltage capabilities, from 500 V ac to 1.2 kVa
    • Surge capabilities up to 200 A
    • Epoxy molding has UL 94 flammability rating of V-0
    • UL Recognized
    • RoHS compliant
    • Passivate junctions reduce current leakage
    • Designed to mount on PCBs with screws or solder
    • Available with several types of terminals
    • Solid state switching eliminates arcing that creates voltage
    • Require small gate activation pulses each half cycle