| 摘要 |
PROBLEM TO BE SOLVED: To control a sound volume with respect to random noise without giving effect onto a path for a main signal or using an analog device for the control of a digitized signal. SOLUTION: Amplitude information equivalent to a sound volume of pseudo noise is stored in advance in a memory 2 and a D0 bit of data of an address designated by an external selection signal and an output of a binary counter 1 is outputted to the binary counter 1 and D1-D7 bits are outputted to parallel/ serial converter 3. The binary counter 1 is reset to an initial value when the data D0 bit of the memory 2 reaches a prescribed value, the binary counter 1 is set to an initial value. The parallel/serial converter 3 converts a random number in 1 bit from the random number generator 4 and the data from the memory 2 into serial data. A D/A converter 5 converts serial data having a random number in 1-bit from the random number generator 4 as a code component into an analog noise output. |
