| 摘要 |
PURPOSE:To deliver a correct signal with simple constitution, by defining a spot where a digital output is fixed before reading the output of a comparator and preventing the output of an erroneous digital signal produced by the difference of the circuit delay time. CONSTITUTION:A reference clock 1 is counted by a counter 31 of an A/D controller 3, and a clock 34 twice as much as the A/D clock 13 is delivered to be divided down to 1/2 by a counter 32. At the same time, the A/D start 12 synchronizing with the clear signal 36 and the clock 34 of the counters 31 and 32 is delivered by an MPX signal 2 that indicates a converting action through a counter 33. Then the clocks 13 and 34 are gated through an AND gate 35, and a holding clock 36 is delivered. The clock 36 is used for the working clocks of the digital output circuit of a converting circuit SAR14 and control circuits 141-150. Recording and fixing are carried out for SAR outputs 15-17 before the output 8 of a comparator 7 is written into the circuit SAR14. Thus an output of an erroneous digital signal which is delivered by the difference of the circuit delay time can be prevented. |
