Semiconductor device

Abstract

When a leakage current of a circuit block under a non-use state is reduced by means of a power switch, frequent ON/OFF operations of the switch within a short time invite an increase of consumed power, on the contrary. Because a pre-heating time is necessary from turn-on of the switch till the circuit block becomes usable, control of the switch during an operation deteriorates a processing time of a semiconductor device. The switch is ON/OFF-controlled with a task duration time of a CPU core for controlling logic circuits and memory cores as a unit. After the switch is turned off, the switch is again turned on before termination of the task in consideration of the pre-heating time.

1 - 9 . (canceled)  
   
   
       10 . A semiconductor device comprising: 
 a processor executing a plurality of tasks, each of the plurality of tasks being executed in time division; and    a plurality of circuit blocks, each of the plurality of circuit blocks being supplied with an operating voltage,    wherein the processor selects at least one of the plurality of circuit blocks for each of the plurality of tasks, and executes each of the plurality of tasks,    wherein the operating voltage supplied to each of the plurality of circuit blocks is controlled according to whether the circuit block is selected or not to execute each of the plurality of tasks.    
   
   
       11 . A semiconductor device according to  claim 10 , further comprising: 
 a plurality of power control units provided at each of the plurality of circuit blocks,    wherein one of the plurality of circuit blocks is selected to execute one of the plurality of tasks, a corresponding power control unit supplies the operating voltage to the one of the plurality of circuit blocks, and    wherein when the one of the plurality of circuit blocks is not selected to execute another one of the plurality of tasks, the corresponding power control circuit cuts off the operating voltage to the one of the plurality of circuit blocks.    
   
   
       12 . A semiconductor device according to  claim 10 , further comprising: 
 a resource management register managing whether each of the plurality of circuit blocks is used or not,    wherein the processor selects the plurality of circuit blocks according to the resource management register.    
   
   
       13 . A semiconductor device according to  claim 10 , 
 wherein the plurality of circuit blocks are supplied with a clock signal,    wherein the clock signal supplied to each of the plurality of circuit blocks is controlled according to whether the circuit block is selected or not to execute each of the plurality of tasks.