A method of acquiring an overshoot voltage applied to a transistor includes determining a first extraction value, the first extraction value including a product of acceleration factors determined in a test of the transistor, determining an applied time, the applied time corresponding to a length of time a voltage deviates from a predetermined level of an input voltage in a circuit employing the transistor, determining a second extraction value by dividing the first extraction value by the applied time, and determining the overshoot voltage by multiplying the second extraction value by the input voltage.