International Business Machines Corporation

Douglas Thomas Massey

Francis A Kampf

Serafino Bueti

Suzanne Granato

Rafael Blanco

John Joseph Bergkvist, Jr

A method for simulating a circuit. The method includes, in response to a first mode change triggering event at a first time point and in response to a first data transfer triggering event at a second time point after the first time point, generating a random value of at least a first random value and a second random value. In response to the generated random value being the first random value, a first input value of an input of the circuit is assigned to an output of the circuit. In response to the generated random value being the second random value, an output value of the output of the circuit is maintained. In response to a second data transfer triggering event at a third time point after the second time point, a second input value of the input of the circuit is assigned to the output of the circuit.

Simulation of digital circuits

A digital circuit simulation method. The method starts with a digital circuit design which includes: a first source latch, a destination latch, a logic cone, a first WAM circuit electrically coupling an output of the first source latch to a first input of the logic cone, and a WAGG circuit electrically coupling an output of the logic cone and an input of the first source latch. Then, a zero-delay simulation is performed in which if a first situation of (a) the first WAM circuit entering an uncertainty state in which the first WAM circuit generates a random value of 1 or 0 at the first input of the logic cone, (b) the logic cone being vulnerable to a positive glitch, and (c) the output of the logic cone being at logic 0, the WAGG circuit generates a random value of 0 or 1 at the input of the destination latch.

Circuit design verification

A method and system for testing a circuit design. The method including generating a simulation model of the circuit design, the circuit design comprising one or more source latches, one or more destination latches and a logic function connected between the source latches and the destination latches; generating a modified simulation model of the simulation model by inserting random skew between an output of each source latch and an input of the logic function only in asynchronous data paths between the source latches and the destination latches of the simulation model; and running the modified simulation model.

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Essex Junction, VT, United States of America

Douglas Thomas Massey