| 摘要 |
PURPOSE:To realize reduction of size and power consumption of a power supply by feeding rectified output prior to conversion, as it is, as well as a DC power supply voltage for a logic circuit, which is converted into a predetermined voltage through a switching regulator, to a switching regulator in a programmable controller thereby producing another DC power supply voltage. CONSTITUTION:In a power supply 1, primary power supply input is rectified and smoothed through a rectifying circuit 10 to produce a rectified output which is then converted through a switching regulator 11 into a DC 5V power supply voltage. Thus produced DC 5V voltage is fed to logic circuits 201-20n in each programmable controllers 21-2n. On the other hand, rectified output is fed from the rectifying circuit 10 in the power supply 1 through a power supply output line 32 to the switching regulators 231-23n in the programmable controllers 21-2n thus producing a predetermined DC power supply voltage which is then fed to process I/O circuits 211-21n. |
