IXYS Corp.’s UK subsidiary UK Westcode Ltd., introduced a new 3.6kV pressure contact phase-control thyristor with increased power density. The improved design offers up to 52% increase in average current rating over the established designs while retaining the overall package footprint. The improvement in performance is achieved by maximizing the die size and an improved package design. The new silicon die is alloyed to a metal disc and encapsulated in a fully hermetic ceramic package. Overall, the new mechanical design presents reduced thermal resistance and the die has enhanced electrical performance.
The new 56mm die device has an average current rating of 1725A and the package has a 50mm electrode contact diameter, with an industry standard overall diameter of 74mm. This new device will ultimately replace two older designs based on 53mm dice. Part designations are N1314NC360 and N1478NC300, offering a respective increase in average current of 31% and 17%. The new thyristors remain mechanically compatible with the old designs and can be used in the same mechanical systems. This new device is also an alternative to the current 50mm die design offering the potential of 52% more current rating in the same mechanical footprint, as long as the cooling and clamping systems are appropriately scaled to accommodate the larger die area.
The new device is available in an industry standard 26mm thick package and two voltage grades. Designations are: N1725MC320 (Vdrm/Vrrm 3200V) and N1725MC360 (Vdrm/Vrrm 3600V). A version of this device optimized for series operation in medium voltage applications will also be available; please consult IXYS UK for details.
Typical applications include soft starters, DC drives and all controlled rectifier applications requiring devices in this power rating.