| 摘要 |
PURPOSE:To deliver a voice without imaring the sound quality with use of a D/A converter having a small number of input bits, by controlling the input contents of the D/A converter after providing a switch circuit. CONSTITUTION:In case no overflow arises for both positive and negative outputs of a register 5, the control terminal C of a transmission gate 9 is set at (0) to deliver B. As a result, (8) bits from the 5th to 12th bits of the output of the register 5 are supplied as they are to a D/A converter 6. In case the overflow of a positive number arises, the output of an NOR gate 10a is set at (1). As a result, the terminal C is set at (1) to deliver A. The output contents of the maximum value is supplied to the converter 6. In the case of the overflow of a negative number, the output of an AND gate 10b is set at (1). Then the terminal C is set at (1) to deliver A. However, the input of the converter 6 is set at the minimum value since the 16th bit of the output of the register 5 is (1). |
