| 摘要 |
PURPOSE:To turn on immediately a lamp after a switch is closed by keeping outputs a comparing circuit, reference voltage generating circuit, and a voltage holding circuit at specific voltage levels before oscillation starts. CONSTITUTION:When the normally open contact 2a of a relay 2 is broken while a turn signal switch 3 is open, high impedance is obtained at a point (d). Therefore, the output of the comparing circuit 1 goes up to a high level and the relay 2 is never energized. At this time, the output voltage of the voltage holding circuit 7 is Vth2 (2nd reference voltage). When the switch 3 is closed at this time, low impedance is obtained at the point (d) to allow the comparing circuit 1 to perform comparing operation, and the output of the holding circuit 7 has high impedance. Further, the point (b) is held at Vth2 because its impedance is low, and a charging and discharging circuit 8 is in a discharge state, so a point (a) is held below Vth2 immediately. Therefore, a point (c) attains to low and the normally open contact 2a is made after the response delay time of the relay 2, and the point (d) attains to high to turn on the lamp load 4 immediately. |
