| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem of a large through-current flowing due to a maximum transition of data, while a ripple counter counts up/down, this causing a noise having adverse influences on neighboring analog circuits. <P>SOLUTION: The counter circuit comprises: a flip-flop circuit 12 composed of three parallel arranged D-FFs 121, 122, 123 with program value loading functions for applying gray codes of 3 bits (b2, b1, b0) converted and given by a code converter circuit 11 for every bit to inputs P of the D-FFs; a logic circuit 13 for executing logical operations on a truth table, for realizing gray counters for outputs of the D-FFs 121, 122, 123 to give the operation result to inputs D of these D-FFs; and an output circuit 14 for taking the logical product of each of the outputs of the D-FFs 121, 122, 123 as a count output, thus suppressing the through-current and the delay in transition of data. <P>COPYRIGHT: (C)2003,JPO |
