| 摘要 |
<p>PURPOSE:To obtain low power consumption characteristics by supplying an oscillation output selected from plural ones outputted from plural oscillating circuits to a timing generator and controlling an arithmetic unit circuit by the output of the generator. CONSTITUTION:Oscillation outputs from the oscillating circuits f1, f2 are supplied in parallel with each other to a selecting circuit 13. The circuit 13 selects and outputs any one of the oscillation outputs f1, f2 in accordance with the level of a control signal SEL. The selected oscillation output is supplied to the timing generator 14 as a reference pulse signal phi. The generator 14 generates various timing signals required for an arithmetic logical operation unit ALU, an instruction register IR, an instruction decoder ID, a memory circuit MEM, an arithmetic processing circuit 15 including an I/O circuit by a means for frequency division or the like of the signal phi. The operation of the processing unit is stopped by stopping the oscillating operation of the selected oscillating circuit.</p> |
