Archive: Institute of Measurement Technology

Sensitive electronic circuits on printed circuit boards to be protected against transient overvoltages require compactly structured nonlinear filters. In particular nonlinear elements in SMD-technology are suitable for this application. There are different discrete and integrated solutions available. On-chip nonlinear protection is available with different types of line drivers and receivers (e.g. for the RS-232 interface). Due to their small volume both discrete and on-chip protective elements have a limited energy absorption. Therefore it is necessary to characterize their behaviour during pulse stresses and to determine their current capability. The linear transfer characteristic has also to be investigated in order to consider effects like attenuation and reflection. Another aspect is the development and evaluation of suitable design strategies to place the components in a space-saving way on the printed circuit board under the constraint of a maximum decoupling. In principle these extra small nonlinear elements can be used especially in all applications, where sensitive electronics have to be protected from transients like ESD, LEMP, SEMP or NEMP and where a minimum of weight and overall dimensions is essential.