Switch assembly for activating a circuit block (11) in an electronic circuit having a plurality of circuit blocks (11-13), comprising: - an on / off switch (14) for turning on / off of a circuit block of the circuit elekronischen, - a detection device (16) which detects when a switched circuit block is to be switched on again, - a control device (15) for controlling a clock signal for the circuit blocks of the switching arrangement, characterized in that when the detection means (16) detects that the power-down circuit block is to be turned on, the control means (15) to the clock for non-energized circuit blocks (12, 13) exposes for a predetermined period, wherein the on / off switch during this period turns on the circuit block (11).