AN3169 Datasheet, PDF (1/12 Pages) STMicroelectronics – Technology performance comparison of Triacs subjected to fast transient voltages

AN3169
Application note
Technology performance comparison of Triacs
subjected to fast transient voltages
Introduction
This paper presents an experimental comparison of several Triac devices under immunity
tests, as described in the IEC 61000-4-4 standard. After a short reminder of the different
Triac technologies available today (Top, mesa and planar technologies), the IEC 61000-4-4
test procedure to compare the devices is explained. The immunity results are discussed
according to the device technology and the gate current sensitivities. A discussion about
relevance of dV/dt parameter and die area is carried on to differentiate the devices in term of
immunity capability.
Home appliances such as washing machines, refrigerators and dishwashers integrate a lot
of low power loads such as valves, door lock systems, dispensers and drain pumps. These
loads are usually powered by the mains in on / off mode, and are mostly controlled by Triacs.
The direct connection of the silicon switch to the mains, through the load, requires that these
devices must withstand line transients to make the system compliant with the international
electromagnetic compatibility (EMC) standards. The silicon devices are then subjected to
fast transient voltages, as described in the IEC/EN 61000-4-4 standard.
The immunity of several Triac technologies is evaluated here experimentally. Several
guidelines can then be pointed out to design high immunity appliances.
March 2010
Doc ID 17194 Rev 1
1/12
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