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IXYS UK Westcode

IXYS UK Westcode are one the of the UK's leading semiconductor manufacturers. Formerly known as Westcode, they launched the world's first commercial rectifier in the early 1920's. Westcode was acquired by IXYS Corporation in 2002, and shortly after changed it's name to IXYS UK Westcode. Today they manufacture high power Thyristor capsules (GTO, fast & standard recovery), Diode capsules (fast & standard recovery) and IGBT capsules.

GD Rectifiers are IXYS UK Westcode’s Official UK Distributor, they stock Europe's largest range of IXYS UK's components, heatsinks and hardware.

For further information, please call: 01444 243 452 or email: .(JavaScript must be enabled to view this email address).

IXYS UK Westcode Thyristors



IXYS UK Westcode offers a broad range of diode products including rectifier diodes, fast recovery, soft recovery, extra fast recovery and high power Sonic FRD’s. Rectifier diodes and soft recovery diodes are both available as capsules or studs.

Rectifier Studs:            428Amps to 735Amps, 1200-3200V
Rectifier Capsules:         507Amps to 9830Amps, 200-5600V
Fast Recovery Capsules:        588Amps to 3770Amps, 200-4500V
Soft Recovery Studs:         130Amps to 336Amps, 1200-2500V
Soft Recovery Capsules:     225Amps to 2413Amps, 800-6000V

Extra Fast Recovery Capsules:    240Amps to 1346Amps, 800-5500V
High Power Sonic FRD Capsules:    208Amps to 4080Amps, 1400-4800V    

View the complete IXYS UK Westcode Diodes range here.



IXYS UK Westcode offers a broad range of Thyristor products to suit your application. These include: Phase Control, Fast Turn-off, Distributed Gate, Medium Voltage and Asymmetric Thyristors. This range includes the new WESPACK outline for Phase Control Thyristors, with voltage ratings up to 2.2kV, giving maximum power rating for weight and volume, without compromising on quality and reliability.

Phase Control Studs:        131Ams to 416Amp, 400-1600V
Phase Control Capsules:        255Amps to 6974Amps, 800-4500V
Fast Turn-Off Studs:        128Amps to 431Amps, 400-1200V – 10 to 30uS
Fast Turn-Off Capsules:        295Amps to 1007Amp, 400-1200V – 10 to 30uS
Distributed Gate Capsules:      472Amps to 4001Amps, 800-4500V – 10 to 300uS
Medium Voltage Capsules:    349Amps to 3503Amps, 3000-6500V
Asymmetric Capsules:        516Amps and 1237Amps, 2400-2800V

View the complete IXYS UK Westcode Thyristors range here.


Thyristor & Diode Modules

IXYS UK Westcode offers a wide range of Thyristor & Diode Modules for isolated heatsink applications and has a UL Certification for most modules. They offer: Standard Circuits, Dual Diode, Dual Thyristor, Single Thyristor or Diode, Common Cathode and Water Cooled versions.

Dual Thyristor Modules:     327Amps to 719Amps, 1200-3600V
Dual Diode Modules:         600Amps to 1080Amps, 1400-3600V
Thyristor Diode Modules:     327Amps to 719Amps, 1200-3600V
Single Thyristor Modules:     765Amps to 830Amps, 1400-2200V
Single Diode Modules:         1520Amps, 1400-2200V

View the complete IXYS UK Westcode Thyristor & Diode Modules range here.


Gate Turn-off Thyristors

IXYS UK Westcode offers a broad range of high specification Stud and Capsule Gate Turn-off Thyristors. IXYS UK Westcode GTO Thyristors incorporate advanced features such as: buffer layer, fine pattern and transparent emitter technologies. Devices with voltage ratings of 6kV (3.8kV DC link) and controllable current ratings of up to 4kA are available to meet the toughest demands in applications such as traction propulsion and auxiliaries, AC industrial drives, FACT's and active VAr controllers. iXYS UK Westcode offer both symmetrical devices for applications with reverse blocking requirement, their GTO Thyristors are still the go-to component for high power converters. 

View the complete IXYS UK Westcode GTO Thyristors range here.


IXYS UK Westcode is also a pioneer of Press-Pack IGBT technology, offering world-class leading devices with voltage ratings of 2.5kV (1.25kV DC Link) and 4.5kV (2.8kV DC link) and have now also introduced its first 6.5kV Press-Pack IGBT. The construction of these devices is totally free from wire and solder bond which all but eliminates the problems of mechanical fatigue associated with conventional IGBT modules.
Details on ratings are available on request.

View the complete IXYS UK Westcode IGBTs range here.


Power Capacitors

IXYS UK Westcode offer a range of power electronics capacitors to suit almost any application form filtering and smoothing DC voltages to GTO/IGBT snubber circuits and medium frequency applications. IXYS UK Westcode also offers a range of bespoke DC-link capacitors, designed specifically for use in application designed to utilise their range of 2.5kV, 4.5kV and 6.5kV press-pack IGBTs.

Power capacitors can be used for a wide range of applications where extremely non-sinusoidal voltages and pulsed currents are present, IXYS UK provide both AC and DC Capacitors. 

View the IXYS UK Westcode Power Capacitors range here.



IXYS UK Westcode’s extensive range of discrete components are used throughout the rail industry and its infrastructure. IXYS offer two types of Custom Built Heatsinks: Air Cooled and Solid Fin Heatsinks. 



Part Number Old Part Number Weight Kg/m Periphery mm Area mm2


XSFGxxxxAN G Fin 8.1 1059 2979 WH1
XSFGxxxxAN GA Fin 15.6 1682 5867 WH2
XSFHxxxxAN H Fin 12.7 1684 4655 WH3
XSFTxxxxAN T Fin 20 2065 7573 WH4
XSFTBxxxxAN TB Fin 29 2467 10905 WH5
XSFTCxxxxAN TC Fin 28 2544 10561 WH6
SXFLPxxxxAN LP100 Fin (40 Vane) 30 6620 11172 WH7
SXF46xxxxAN  WS46 Fin 20 2822 7411 WH8
SXF30xxxxAN WS30 Copper Fin Dimensions 125mm x 125mm x4 vanes WH9

For further information on all IXYS UK Westcode products, email us or call: 01444 243 452.

IXYS UK Westcode

IXYS UK Westcode, formerly Westcode Semiconductors has been at the forefront of power semiconductor design. Supporting a truly worldwide and diverse market place, IXYS UK Westcode has evolved in to one of the world's leading manufacturers of high power semiconductors. 

Further information:

You can find further information on IXYS UK Westcode using the following links:

Tel: 01444 243 452

Fax: 01444 870 722

Email: enquiries@gdrectifiers.co.uk