Cross referencing is normally applicable only for devices of the same P PP rating for equivalent TVS performance levels. Both parts share essentially the same electrical characteristics and DO-214AA package outline although marked with different labels. This exercise in equivalent selection provides guidance to the user in choosing alternative sources and also allowing for broader supplier base. Illustrated below is an example cross referencing an axial lead 1.5 kW device for operating in a 36 V circuit to an electrically equivalent surface mount chosen from the Microsemi Product Data Book. Subsequently, the remaining parameters were also a close match for the same 1.5 kW device rating.
Some parameters match more closely than others.
In most cases, especially for ESD protection, the V WM can be as high as 15 V for a 5 V operating circuit and still provide good performance. This has been proven in volume production. In the event that a perfect match cannot be made, integrated circuits are normally quite forgiving for very short duration pulses, even though a substitute TVS may clamp a few volts higher. If you need additional guidance in cross referencing devices or in selecting a TVS for your application, please call Microsemi Corp. - Scottsdale for assistance.