Detecting operating conditions

A system comprising:

• a functional circuit;
• and
• a detector cooperating with said functional circuit and comprising
• a delay line comprising a plurality of delay elements and configured to have at least one first delay value corresponding to a first operating condition of said functional circuit and at least one second delay value corresponding to a second operating condition of said functional circuit,
• a monitoring circuit configured to monitor a time taken for a first clock edge of a clock signal to propagate through said delay line and comprising
• a first plurality of flip-flops, an output value of each delay element being configured to clock a respective one of the first plurality of flip-flops,
• each first flip-flop having a data input, and a data output, said data output being coupled in feedback with said data input, and
• a determining circuit configured to determine whether a current operating condition of said functional circuit is acceptable based upon the time taken for the first clock edge of the clock signal to propagate through said delay line.

A method for determining a current operating condition of a functional circuit with a detector cooperating with the functional circuit, the method comprising:

• transmitting a clock signal through a delay line in the detector, the delay line comprising a plurality of delay elements, a first clock edge of the clock signal being delayed by the delay line by a first delay value under a first operating condition of the functional circuit and by a second delay value under a second operating condition of the functional circuit;
• monitoring, via a monitoring circuit in the detector, a time taken for the first clock edge of a clock signal to propagate through the delay line, the monitoring circuit comprising
• a first plurality of flip-flops, an output value of each delay element being configured to clock a respective one of the first plurality of flip-flops,
• each first flip-flop having a data input, and a data output, the data output being coupled in feedback with the data input;
• and
• determining, via a determining circuit in the detector, whether the current operating condition of the functional circuit is acceptable based upon the time taken for the first clock edge of the clock signal to propagate through the delay line.