Electronic circuit configured for indicator case

DETAILED DESCRIPTION It is an object of the present invention further to develop an electronic circuit for an instrument cluster in such a manner that the effects of both line-related and non-line-related interference are counteracted and that the wireless propagation of outgoing radio-frequency interferences is reduced.
It is another object of the invention that the required depth of installation of the electronic circuit be kept as small as possible, that its structural dimensions be kept small and that the mounting be simplified.
In this connection, the electromagnetic compatibility is to be improved and dissipated heat which occurs is to be led off well to the environment.
At the same time, the reliability of operation is to be increased and, in particular, the heat removal is to be improved in view of the close arrangement of the heat-generating components.
Finally, it is to be possible to produce the electronic circuit, and thus the instrument cluster as a whole, in a simple and inexpensive manner.
According to the invention there is provided an electronic circuit for an instrument cluster in a motor vehicle, the circuit being constructed with at least one ceramic substrate provided with component parts in a shielding housing.
In addition, the invention provides that a part of the surface (32) of the ceramic substrate (e.
g.
31, 63) is kept free of components and can be brought into areal contact with a substantially congruent surface (48) which is recessed in an outer surface of the shielding housing (35).
It is advantageous in this connection that the invention measures extend only over a part of the instrument cluster and therefore entail only slight expense.
It is furthermore advantageous that the previous construction of an instrument cluster need not be fundamentally changed.
It is also advantageous that the electromagnetic compatibility be improved.
It is finally advantageous that the lost heat which occurs is led away well to the environment.
According to a feature of the invention, the areal contact takes place with the interposition of an adhesive which is a good electrical conductor