How do I start selecting an IXYS device?

Fix the voltage class from your DC bus, size the current for the worst-case load, then choose the device type for the function: a MOSFET or IGBT to switch, a thyristor to control or rectify, and a fast recovery diode for the freewheeling path. Finally pick the package for your cooling. Those decisions narrow the catalog quickly.

MOSFET, IGBT or thyristor: which should I choose?

Choose a MOSFET for fast switching and simple voltage-gate drive at low to medium voltage. Choose an IGBT for high-voltage, high-current switching where its low saturation voltage wins. Choose a thyristor for phase control, soft-start and rectification, where surge capability matters more than fast turn-off. Many systems use more than one type.

Can BeiLuo help finalize my device choice?

Yes. Send your voltage, current, switching frequency and topology and we will propose a shortlist with loss, thermal resistance and stock status, then support design-in. Getting the device right saves project time.

What selection mistakes should I avoid?

The usual mistakes are oversizing current, ignoring the thermal path and choosing a package that does not fit the heatsink. Each adds cost or risk without benefit. Validate the choice on the bench before committing the BOM.

How do I drive an IXYS IGBT?

An IGBT has a MOS gate, so it is driven with a voltage like a MOSFET, but the gate resistor and dead time must be set for the switching speed you need. A negative off-state supply improves robustness in a half bridge. Keep the gate loop short and verify turn-off overshoot at the device terminals.

HiPerFAST or ultra-low VCE(sat)?

Choose HiPerFAST (the C2 family) for higher switching frequency where switching loss dominates. Choose the ultra-low VCE(sat) part for lower frequency and high current where conduction loss dominates. The two families let you trade loss for the application. Our FAE team can compare them at your operating point.

How do I set the dead time?

Dead time must be long enough to prevent cross-conduction in a half bridge but short enough to avoid output distortion. Verify it on the bench with a current probe on the phase output, and account for the gate-drive propagation delay. Our FAE team can review your gate-drive design.

How do I handle the freewheeling path?

Pair the IGBT with a fast recovery diode such as the DSEI60-06A for low recovery loss or the softer DSEP60-06A for lower EMI. Match the diode current and recovery charge to the switch and switching frequency. Get a matched switch and diode pairing.

My thyristor will not turn on. Where do I start?

Check the gate drive first: the gate current pulse must exceed the datasheet gate trigger current, arrive within the correct window, and match the gate polarity. Then check the anode voltage and the load. A missing trigger or a wrong firing angle is the usual cause of a no-turn-on. Measure the gate waveform with a scope at the module terminals.

The module fails at power-up. Why?

A power-up failure is usually a surge or a dv/dt problem. Check the inrush current against the surge rating, and confirm the snubber limits dv/dt below the datasheet value. A missing or mis-sized snubber lets the device turn on spuriously and fail. Measure the inrush and the dv/dt across the device.

How do I prevent false triggering?

False triggering comes from excessive dv/dt across the device, so the snubber and the layout are the levers. Keep the gate circuit low-impedance, add a gate-cathode resistor, and size the RC snubber for the worst-case commutation. Our FAE team can review your snubber design.

The module runs hot. What should I check?

On-state loss scales with the on-state voltage times the average current, and the surge duty adds to it. Check the actual current waveform, the thermal interface and the heatsink, and confirm the rating at the expected case temperature. A thick or uneven interface is a frequent culprit. Request a thermal design review.

What is the standout feature of IXYS HiPerFET MOSFETs?

The HiPerFET process combines a rugged, avalanche-rated body diode with fast switching and low on-resistance, so the device tolerates the inductive loads and transients of real equipment. The isolated SOT-227B package also makes multi-device heatsinking simple. The main design care point is the gate loop and the thermal path.

Why does the SOT-227B package help?

The SOT-227B is an isolated, screw-mountable package with a large thermal pad, so several devices share a heatsink without an extra insulating layer. That simplifies assembly, improves heat transfer and raises the power a single heatsink can handle. It is common in supplies, inverters and welding equipment.

How do I use the body diode?

The HiPerFET body diode is fast and avalanche-rated, so it freewheels cleanly in a bridge. For heavy freewheeling or lower loss, a parallel fast recovery diode such as the DSEI60-06A reduces the loss further. Match the diode current to the freewheeling current. Get a matched MOSFET and diode pairing.

Can I get samples to evaluate?

Yes. We provide samples of the HiPerFET MOSFETs for your own efficiency and thermal testing, with documentation included and FAE support during bring-up. Request a sample and we will confirm stock and lead time.

Technical Support | IXYS Expertise | BeiLuo

Guides, application notes, troubleshooting and reviews from BeiLuo's FAE team covering IXYS power MOSFETs, IGBTs, thyristor modules and fast recovery diodes.

Guides 1 Application Notes 1 Troubleshooting 1 Reviews 1

How to Select an IXYS Power MOSFET, IGBT or Thyristor

2026-07-27 - Guides - By Wei Zhang

Compare IXYS power MOSFETs, IGBTs, thyristor modules and fast recovery diodes by voltage class, current and package to choose the right device for your converter.

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IXYS IGBT Application Notes: Gate Drive and Thermal Design

2026-07-20 - Application Notes - By Wei Zhang

Gate-drive, dead-time and thermal guidance for designing motor drives, UPS and high-frequency supplies around IXYS HiPerFAST and ultra-low VCE(sat) IGBTs.

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Troubleshooting IXYS Thyristor Modules in Phase Control

2026-07-10 - Troubleshooting - By Daniel Cross

A systematic method for diagnosing gate-drive, commutation, dv/dt and thermal problems in IXYS thyristor SCR modules used in phase-control and rectifier circuits.

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IXYS HiPerFET Power MOSFETs: A Practical Review

2026-06-30 - Reviews - By Mark Sullivan

A hands-on review of IXYS HiPerFET power MOSFETs for supplies, PFC and inverters, covering ruggedness, the body diode, switching and package practice.

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Meet Our FAE Team

Wei Zhang

Senior FAE Engineer, Power Devices

IGBTPower MOSFETGate Drive

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Daniel Cross

FAE Engineer, Thyristors

ThyristorRectifiersProtection

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Mark Sullivan

FAE Engineer, Applications

Power MOSFETEfficiencyThermal

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