| 摘要 |
PURPOSE:To decrease the number of times of a clock of a flip-flop circuit by adopting the constitution making the clock effective only when a data of the flip-flop circuit is changed. CONSTITUTION:An exclusive OR circuit A detects a change in a data DATA with respect to an output Q and outputs a '1' level only when the data DATA differs from the level of the output Q. Thus, a NAND gate B receiving a clock CLK makes the clock CLK effectively only when the data DATA is changed by a signal (a) outputted from the exclusive OR circuit A. When the clock CLK is read and the data DATA appears at an output Q, since the level of the data DATA and the output Q is the same, the exclusive OR circuit A is returned to a 'O' level. Thus, the clock CLK is clamped by the signal (a) and cannot pass through the NAND gate B until the data DATA changes again. |
