| 摘要 |
PURPOSE:To obtain a phase controller which eliminates the need to provide a voltage level detecting circuit individually by composing the phase controller of a reference pulse detecting circuit, input voltage detecting circuit, control angle arithmetic device, and trigger pulse generating circuit. CONSTITUTION:The reference pulse detecting circuit 11 discriminates the level of an input voltage by a reference level whose pulse width depends upon the input voltage and generates a reference pulse. This reference pulse is sent to a differentiating circuit 12 to detect its rise and fall. A pulse-width measuring timer 13 measures the width theta of the reference pulse and a signal indicating the pulse width theta is sent to the input voltage detecting circuit 14, where the input voltage V is calculated. The control angle arithmetic device 15 calculates a control angle alpha according to the input voltage V so that a given control value E is satisfied. The trigger pulse generating circuit 18 outputs a trigger pulse with constant width when a time-up signal corresponding to a control angle beta is supplied from the device 15. Thus, the need to provided the voltage level detecting circuit individually is eliminated. |
