| 摘要 |
<p>A circuit for reducing the average light emitting diode (LED) (18) current required to latch an output triac (22). A ring oscillator (14) coupled to a logic means (16) provides a current pulse to the LED (18) that triggers the optically coupled output triac (22) early during each half sinewave. A biasing means (12) for determining the current pulse duration is coupled between the ring oscillator and a.c. and d.c. input terminals.</p> |
