| 摘要 |
PURPOSE:To speed up circuit operation and simplify a circuit by using a generating circuit for a reference voltage which varies abruptly at the beginning and then varies slowly in a polygonal shape in common to respective channels. CONSTITUTION:An AD converter for a multichannel digital recording and reproducing device is provided. Then, two inputs L1 and R1 are held by sample holding circuits 20A and 20B respectively, compared with a ramp voltage by comparators 24A and 24B, and converted into time width values intermediately; and counters 25A and 25B count clocks from clock generators 26A and 26B, thereby outputting a digital signal 23. Then the ramp voltage is used in common to respective channels, and stepped linearly and abruptly down to a voltage VS from an initial state VE and then slowly down to a voltage VT in the polygonal shape. |
