| 摘要 |
An electrical load in series with a source of AC power is connected across the anodes of a triac with the secondary of a transformer being connected between the triac gate and one of the triac anodes. An electronic switch controls current flow in the primary of the transformer such that a negative voltage is supplied at the gate of the triac during conduction by the primary until saturation of the transformer occurs. After saturation, the electronic switch opens the transformer primary initiating a flyback period during which the triac gate potential rings positive and a consistent peak positive current is supplied to the triac gate from the secondary of the transformer. A half-wave rectifier circuit and transistor may be substituted for the triac for DC load control, or a pair of these transistor circuits may be connected in series to provide AC load control.
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