CLOCK MODULATION DEVICE

PROBLEM TO BE SOLVED: To prevent a system clock signal of a digital system from exceeding its allowable maximum interference value by adapting a clock modulation device to the system in dependence on the interference spectrum of the system clock signal for the reduction of amplitude of an interference spike. SOLUTION: An oscillator 1 produces a basic clock signal 2. The signal 2 is modulated into a system clock signal 4 by a clock modulation device 3 and used to drive a digital system 5 which includes a microprocessor and/or another digital module. The device 3 is adapted to the system 5 by selecting a tap by means of a random number that is suitably generated by a random number generator, controlling the delay time by a controller via a control line and/or changing the designation of allocation of a switching element via the control line.