| 摘要 |
<p>A power supply includes a digital controller (10) which generates pulse-width modulated control signals for controlling the duty cycles of switching transistors (36) for the purpose of regulating the output voltage of the power supply. In order to generate the control signals, the controller includes an adding circuit arranged to add a digital value representing a standard pulse-width modulated control signal to another digital value dependent on the difference between successive digital values each representing an instantaneous value of an output voltage level of the power supply. The controller also includes circuits for controlling a starting up routine for the power supply and for selecting an operating switching frequency. Since the controller is digital in construction, integrated circuit chips may be used so that the power supply is of simple construction and of low cost.</p> |
