Circuit arrangement and measuring method for determining the behaviour of electronic circuits when the supply voltage is disturbed

摘要

Between the output of a first operational amplifier provided for the injection of interference signals and at least one power supply input of an electronic circuit to be measured, a second operational amplifier is connected. The output of the latter is connected to a complex impedance by means of which the internal impedance of the interference voltage source can be variably simulated. By this means, the value of the internal impedance of the interference voltage source is first set to 0 and then the values of the disturbances appearing at an output of the electronic circuit and impressed on an input signal are measured. The value of the complex impedance is then changed until the values of the interference variables have dropped to half the previously measured value. At this setting, the value of the complex impedance corresponds to the internal impedance of the electronic circuit with the given type of disturbance.