| 摘要 |
PROBLEM TO BE SOLVED: To make consumption current to be low without deteriorating operation speed by setting the operation rate of a part operated by an inverse code pattern to be half and sharing a unit with a common full adder operating independent of the inverse diffusion code pattern. SOLUTION: An inverse diffusion code generation part 71 generates inverse spread code groups 701-70n whose phases are shifted by one chip based on a reference clock and outputs a control signal 700 to a selector 31. Whenever a reception signal 100 is inputted, a FIFO memory 11 outputs a past signal by n-chips from the reception signal 100 at present as FIFO output 109. A full adder 80 adds a difference between the input signal 100 which is inputted this time and FIFO output 109 to an accumulation result. Partial adders 81-8 accumulate the signals when the inverse spread code groups 701-70n are '1' or '-1'. Thus, consumption current can be set to almost 1/2 with a condition that a spread rate (n) is sufficiently large. |
