Testable circuit

摘要

A testable circuit comprises a signal path having a time-dependent response behavior (for example, a high-pass filter behavior). The signal path is tested for faults. To this end, the circuit is switched to a test mode in which the signal path is isolated from other signal paths. Subsequently, a test signal containing a signal transition is applied to the input of the signal path and it is tested whether the signal on the output of the signal path at any instant exceeds a threshold level during a predetermined time interval after the transition. The result is loaded into a register and read from the circuit.