Colorful loop decorative lights

The lamp circuit design is novel, the structure is simple, the cost is low, and the fun is strong. It can be used as an advertising lamp in hotels and restaurants, and is also suitable as a festival lantern. This lantern is based on the principle of three primary colors, using three primary colors of red, green and blue to form a variable color unit. Put the three primary color lamps into the frosted glass cover, and use the color mixing effect of the lamp cover (the color mixing principle is: red + green = yellow, blue + red = purple, green + blue = cyan, red + blue + green = white ) displays seven colors in the external loop, namely red, blue, green, purple, cyan, yellow, and white. Working principle: The circuit of the colorful decorative lamp is as shown in the figure: 220V AC is stepped down by C1, stabilized by DW, rectified by VD, filtered by C2 and then outputs 12V DC voltage for the control circuit to work. IC1 time base integrated circuit NE555 and R1, RP, C3 form an adjustable clock pulse generator to provide the required clock pulse signal for the subsequent circuit. IC2 is C180, which is a COMS integrated circuit with synchronous addition and counting function. Its reset terminal (R) is connected to C5 and R2, so that the circuit automatically clears and resets every time the power is connected. CP is the clock pulse input terminal, Q1~Q4 are the output terminals, and the output logic state is shown in the truth table. As can be seen from the table, when the first clock pulse is input from the CP terminal of C180, its Q1 terminal output is high level, the transistor V1 is turned on, and the triac SCR1 is triggered to turn on, and the first primary color bulb H1 Lights up, and the lampshade displays red; when the second clock pulse triggers C180, its Q2 output is high level, V2 and SCR2 are turned on, the second primary color bulb H2 lights up, and the lampshade displays green. When the third clock When the pulse triggers C180, the Q1 and Q2 terminals output high level at the same time, V1, V2, SCR1, and SCR2 are all turned on, and H1 and H2 light up at the same time. According to the color mixing principle, the lampshade displays yellow; when the fourth clock pulse triggers C180 , the Q3 terminal outputs high level, the third primary color bulb H3 lights up, and the lampshade displays blue. By analogy, the outputs of Q1, Q2, and Q3 of C180 form 7 logical states, which can make the three primary color lamps H1, H2, and H3 mix in 7 colors, so the lampshade can display 7 colored lights. When the 8th clock pulse triggers C180, Q4 outputs high level, C180 is reset, and the circuit starts to cycle the above process again. S is the color fixing switch. If you need to fix which color, just turn off the switch S. Output clock Q4 Q3 Q2 Q1 1 0 0 0 1 2 0 0 1 0 3 0 0 1 1 4 0 1 0 0 5 0 1 0 1 6 0 1 1 0 7 0 1 1 1 8 1 0 0 0 C180 truth table Component selection and installation: RP selects a 470K potentiometer, which can adjust the color cycle rate of the lamp. C1 uses a metal film paper dielectric non-polar capacitor with a voltage resistance of 400V. DW uses a 12V Zener diode. Three bidirectional thyristor CSRs are selected with a withstand voltage of 400V. Other components are selected as marked in the figure. During installation, the colored lights H1~H3 are fixed in the lampshade, and other components are installed in a small plastic box. Fix the RP potentiometer and color fixing switch S on the panel of the small plastic box for easy control. In addition, when welding the CMOS integrated circuit C180, the soldering iron must be reliably grounded to prevent damage to the integrated block.