Abstract: An alarm chip (10) and the use of the alarm chip (10) for giving warning of burglary or undesired entry into buildings, installations or structures, preferably by so-called shell-protection of the building, installation or structure, the alarm chip (10) detecting, by means of an associated accelerometer, motions/vibrations in the object to which the alarm chip (10) is fixedly arranged, the object being formed of e.g. a window (2), a door, possibly a frame or casing connected to the window (2) or door, wherein the motions/vibrations are converted by means of the accelerometer into an outgoing flow of acceleration values, which are further processed, by means of a processor in a signal processing circuit, in which, by means of algorithms, the acceleration values are recognized and separated into either output alarm signals or output non-alarm signals, and in which output signals may be coded/encrypted, so that each alarm chip (10) has i.a.