1、5500汉字, 4000 单词, 2 万英文字符 Switching power source with a digital control circuit A switching power source having a digital control system is provided. The switching power source includes a switching circuit 40 for switching an input power, an output circuit 50 for converting the switching output into
2、a DC output, and a digital control 70. The digital control 70 is adapted to receive an output voltage analog signal AS1 and an output current analog signal AS2, and to convert the signals AS1 and AS2 into digital signals. It further functions to calculate, based on the digital signals, a command val
3、ue for determining at least one of the switching frequency and the on or off time of the main switch 42. The operation of the main switch 42 is controlled in accordance with the command value. Information on power source input voltage or load terminal voltage is obtained through an assumption based
4、on the signals AS1 and AS2. FIELD OF THE INVENTION The present invention relates to a switching power source arrangement. More particularly, the present invention relates to a switching power source arrangement including a switching circuit for switching input electric power to produce an output of
5、a pulsating wave form, the pulsating output produced by the switching circuit being then converted into a DC output, the DC output being monitored by a control circuit which is adapted to control the switching circuit so that a substantially constant DC output voltage is maintained. More specificall
6、y, the present invention pertains to a switching power source arrangement having such control circuit comprising a digital circuit. BACKGROUND OF THE INVENTION In conventional switching power source arrangement, it has been common to provide such control circuit with an analogue circuit. In this instance, the output voltage and the output current are detected in terms of analogue signals which are processed in the form of analogue values, the results of the processing being used to produce co