SEMICONDUCTOR INTEGRATED CIRCUIT AND PORTABLE ELECTRONIC EQUIPMENT USING THE SAME

PURPOSE:To save current for precharging and to reduce the current consumption of a microprocessor in operation by precharging only a divided instruction decoder corresponding to an instruction to be decoded. CONSTITUTION:The signal line-4 in an instruction signal group 5 which corresponds to the MSB(most significant bit) is connected to a precharge decoding circuit 7, and precharge 3 is inputted to the other input of the precharge decoding circuit 7. The outputs of the precharge decoding circuit 7 are signals 12 and 13 and connected to precharge control transfer groups 9 and 10, which are connected to instruction decoders 1 and 2. This precharge decoding circuit 7 activates the precharge signal 12 or 13 corresponding to a currently inputted d instruction and controls the precharge control transistor group 9 or 10.