Automatic hand washing machine circuit diagram

The circuit principle of the automatic hand washing machine is shown in Figure 1. The 220V AC circuit is stepped down by the transformer T and becomes low-voltage AC. After rectification and filtering, it becomes low-voltage DC. It is then stabilized by the three-terminal integrated voltage stabilizing circuit 7806 to obtain 6V DC power to supply the control circuit. H1 is a red light-emitting diode, used as a power indicator. N2 is the infrared receiving circuit SFH506-38, N3 is the phase-locked loop audio decoder LM567, N3, R3 and C6 form an oscillator, R3 and R6 determine the center frequency of the internal voltage-controlled oscillator of N3, and pin 3 of LM567 is the signal input terminal, pin 8 is the logic output terminal, and its output terminal is the OC gate output. The maximum sink current is 100mA. The operating voltage of LM567 is 4.75V~9V, the operating frequency can be from a few tenths of Hz to 500 kilohertz, and the quiescent operating current is 8mA. . N4 is the NE555 timer, which forms a monostable timing circuit with peripheral components. Its purpose is to ensure the normal water discharge of the handwasher when the human hand occasionally deviates from the infrared detection range.