4h AC power timer (555, BH4024) circuit

(1) Introduction to circuit principle Figure 3-14 shows a 4h AC power supply timing circuit. in this circuit. BH4024 is a 7-level binary serial
counter/frequency divider. 555 is a time base circuit. AN is the timed touch button. Each time AN ​​is pressed, AC power is output for 4 hours.
Then the power is cut off. This circuit can be used to supply power in 4h mode during the unit's working hours in the morning and afternoon.
    (2) Component parameter selection The selection of components is shown in Figure 3-14, and there are no special requirements.
    (3) The 4h AC power timer (555, BH4024) circuit is shown in Figure 3-14.