| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit device generating an initial value of a high quality pseudo random number sequence in which randomness is determined on the basis of a plurality of factors with a simple circuit configuration.SOLUTION: A semiconductor integrated circuit device includes: a power-on reset circuit detecting rising of a power source voltage, temporarily activating a reset signal and subsequently deactivating it; a first oscillation circuit outputting data sequentially varying by performing oscillation operation and stopping the oscillation operation when the reset signal is deactivated; a second oscillation circuit outputting a clock signal by performing the oscillation operation at an oscillation frequency lower than an oscillation frequency of the first oscillation circuit and stopping the oscillation operation when the reset signal is deactivated; and a shift register outputting data of a predetermined bit-number as an initial value of a pseudo random number sequence when the reset signal is deactivated by synchronizing the data output from the first oscillation circuit with the clock signal and sequentially holding them.SELECTED DRAWING: Figure 2 |
