Patent ID: 8055924

Claim:
A semiconductor integrated circuit, comprising: a plurality of function blocks; a CPU; a power supply control unit to which electric power of a power supply is continuously supplied, and which controls supplying of electric power of the power supply to said plurality of function blocks and said CPU; a plurality of switch units controlled by said power supply control unit, for switching an electric power supplying operation of the power supply and an electric power cutting off operation thereof with respect to each of said plurality of function blocks and said CPU; and a power supply cutoff solving unit for varying a signal which is inputted from one function block to another function block, which are contained in said plurality of function blocks, wherein: said power supply control unit stores a control content corresponding to either an interrupt issued from any one of said plurality of function blocks or an instruction issued from said CPU, in response to one of said control contents, said power supply control unit controls each of said plurality of switch units so as to initiates at least one of said plurality of function blocks and said CPU, and said power supply control unit controls said power supply cutoff solving unit in such a manner that a level of a signal is forcibly fixed to a low level, while said signal is propagated from a function block whose power supply is cut off to a function block to which electric power of the power supply is supplied.