Patent ID: 7110932
Filing Date: 2006-09-19
Classification: H03K

Abstract:
1. A method of determining an indicator of a signal transit time in a digital circuit by use of an auxiliary circuit associated with and simulating the digital circuit, the auxiliary circuit having at least two replicas of a signal path in the digital circuit made up of circuit elements connected in series, wherein mean signal transit times in the circuit elements of a signal path replicas bear a known relationship to mean signal transit times in circuit elements of a signal path of the digital circuit that is simulated, and wherein the at least two signal path replicas and the digital circuit are connected to the same supply voltage, the method comprising: subjecting the signal path replicas and the digital circuit to the same operating conditions; determining a mean of the signal transit times on the signal path replicas; and setting the mean plus an added temporal safety margin as the indicator of the signal transit time in the digital circuit.