Combination lamp lighting circuit

The chandelier control circuit introduced in this article can control the working status of the three groups of bulbs in the chandelier respectively , so that the three bulbs can light up at the same time or light up
and extinguish independently.
    Circuit working principle: The chandelier controller circuit consists of a power supply circuit, a trigger control circuit and a control execution circuit.
In the circuit shown in Figure 16-17, the power supply circuit consists of a step-down capacitor G, a bleeder resistor R6, a Zener diode vs. , rectifier diode VD and filter capacitor G
; the trigger control circuit consists of control button s, counter integrated circuit Ic, and resistor R:. Rs and capacitors Cl, cz; the control execution circuit
consists of resistors R7-Rg and thyristor VTH1. Composed of VTH3. The AC 220V voltage is stepped down by C4, stabilized by vs, rectified by VD and filtered by C3
to provide 9V DC voltage for the IC.
    lC is cleared and reset after power on, and its output terminals (⑥, ⑤, ④ and ③) all output low level , causing the thyristors VTH1 and
VTH3 to cut off, and the three sets of light bulbs (EL1, EL2, EL3) Bright.
    When s is connected continuously, pin ① of Ic will continuously input positive pulse signals, and its output terminals (pin ⑥, ⑤, ④ and ③) will press the binary system
from 0001 to 1000 (0 is low level, 1 is high level). flat) sequential output. Pins ③, ④, and ⑤ of the IC
are connected to the door panels of VT3, VT2, and VT1 through selenium, wind, and R respectively. When a certain output terminal of 1C outputs a high level, the thyristor controlled by the output terminal will conduct Pass. That is,
when the ③ pin of IC outputs high level. VTH3 is turned on when triggered, and the third bulb EL3 lights up; when the ④ pin of 1C outputs a high level, VTH2
is turned on ÷ the second bulb EL2 lights up; when the IC's ⑤ pin outputs a high level. VTH1 is turned on, and the first bulb EL1 lights up.
    The ⑥ pin of lC is connected to the ⑦ pin (reset terminal). When the ⑥ pin outputs high level, lc is reset, and each of its output terminals becomes low level . At this time,
VTH1-VTH3 are all cut off, and all 3 bulbs are extinguished.
  There are 7 combination states of the 3-way light bulbs. In addition to being able to light or extinguish independently, the 3-way light bulbs can also light up at the same time.