汽车门窗玻璃上升和下降定时控制电路如图所示，定时范围在208以内连续可调。其工作原理为：（】）稳定常态接通电源后不久，电容器已和CZ的电压为零，555的第7脚内部与第！脚均导通，第3脚输出低电子，于是LEDI和LEDZ均发光指示，继电器1．和人释放，它们的常开接点为常开，常 Car doors and windows ascending and descending timing control circuit shown, the timing range of 208 continuously adjustable. Its working principle is: (】) The steady state power supply soon after the capacitor has been and CZ voltage is zero, 555 of the first seven feet and the first! Feet are turned on, the first 3 feet output low electron, so LEDI and LEDZ are luminous instructions relay 1. And the release of people, their normally open contacts are often open, often