| 摘要 |
PURPOSE:To reduce the power consumption of a semiconductor by supplying a shift register with a transfer clock signal from a transfer clock signal source only when there is data in response to the output of a data presence/absence detecting means. CONSTITUTION:Outputs Q of flip-flops F1-F11 are led out in series successively every time a transfer clock signal is inputted, and stored in the flip-flops F1- F11 after a signal with logic 1 is transferred from the signal source 4. Then when the signals stores in the flip-flops F1-F11 are all transferred in series and their storing contents are all logic ''1'', the outputs Q of the flip-flops F1- F11 are received by an AND circuit 5, which outputs logic ''1'' to reset a flip- flop F12. Consequently, a transfer clock signal Txc from an AND gate 1 is cut off. Therefore, the transfer clock signal is not used any more after the data are transferred, and the power consumption is reduced. |
