Impedance mismatch detection circuit

An electronic system, comprising:

• at least one integrated circuit, the at least one integrated circuit including at least one comparison circuit for detecting impedance mismatch between pull-up and pull-down devices in a circuit to be monitored, the at least one comparison circuit comprising:
• a comparator operative to receive first and second signals and to generate, as an output of the comparison circuit, a third signal indicative of a difference between the first and second signals;
• a first signal generator connected with a first input of the comparator and operative to generate the first signal indicative of a difference between reference pull-up and pull-down currents that is scaled by a prescribed amount, the reference pull-up current being indicative of a current flowing through at least one corresponding pull-up transistor device in the circuit to be monitored, the reference pull-down current being indicative of a current flowing through at least one corresponding pull-down transistor device in the circuit to be monitored;
• and
• a second signal generator connected with a second input of the comparator and operative to generate the second signal as a reference voltage defining a prescribed impedance mismatch threshold associated with the circuit to be monitored.

A comparison circuit for detecting impedance mismatch between pull-up and pull-down devices in a circuit to be monitored, the comparison circuit comprising:

• a comparator operative to receive first and second signals and to generate, as an output of the comparison circuit, a third signal indicative of a difference between the first and second signals;
• a first signal generator connected with a first input of the comparator and operative to generate the first signal indicative of a difference between reference pull-up and pull-down currents that is scaled by a prescribed amount, the reference pull-up current being indicative of a current flowing through at least one corresponding pull-up transistor device in the circuit to be monitored, the reference pull-down current being indicative of a current flowing through at least one corresponding pull-down transistor device in the circuit to be monitored, the first signal generator comprising:
• a reference pull-up current source connected in parallel with a first pull-down device coupled between a first voltage supply and a second input of the comparator;
• and a reference pull-down current source connected in parallel with a first pull-up device coupled between a second voltage supply and the first input of the comparator;
• and
• a second signal generator connected with the second input of the comparator and operative to generate the second signal as a reference voltage defining a prescribed impedance mismatch threshold associated with the circuit to be monitored.