Digital circuit sound and light control stair delay switch circuit (6)

It is a sound- and light-controlled stairway extension lighting system with good performance. The circuit has high
anti-interference performance and ensures soft start and over-current protection functions.
    Ri. The photoresistor is low during the day. Resistor, gate Ⅲ input terminal ① pin is low level,
after two stages of inversion, @ pin is also at slug level , vm is reverse biased and cut off. At this time, f JV output terminal, ⑧ pin, is low level, thyristor
VT Turn off, the lamp E will be lit for a while. The RI. is a high resistance, adjust the resistance of R, and R. in advance
so that the voltage of pin ① is still below the 1/2Vmf J circuit flip threshold level. This The circuit state will not change,
but it has a higher control trigger sensitivity. Gate I constitutes a linear amplifier, and the above process is the same as 5 and 1.
When I{ feels the sound wave signal, pin ⑩ can output a positive The rectangular 7-shaped wave is coupled through (1.), causing the ① pin to become a high level,
causing the circuit state to flip, and the voltage uE to light up.
    This circuit's gate gate and gate IV OR form a Schmitt trigger, and its function Yes: it can shape the trigger signal
and eliminate interference pulses; together with R., it forms a level comparator, which can adjust the light control circuit, so that when the light
is strong , the circuit can always be in the reset state. and 0 form a delay circuit. The data delay time in the picture is about
2js. Ri., (j form a soft-start circuit. When the lights are turned off, the ⑥ pin is high level, and C and L/ are allowed to be fully charged. When there is a sound
at night , ⑥ pin is low level, G discharges to R. The discharge time is very short, about 1.5s, so that ⑨ pin
changes low level, turning on the thyristor VT. Overcurrent protection circuit H VD7.R. R. Composition, R. is the sampling and current-limiting
resistor. If VT is turned on, the bulb I: has moderate power, R. r-voltage drop is low, not enough to turn on VD7. ⑧ pin
is always high level , the bulb point On until the delay time set by R., (3 is over. Door! - Door VI uses a
CD4069 six-inverter digital integrated circuit. E should use an incandescent bulb of 60W or less. If
the power of E is too high, the circuit It will ignore the overcurrent protection function and make the jLi light go out in vain.
  Increase or decrease R, and the value can adjust the sound sensitivity of tU. The larger the resistance, the higher the sensitivity, and vice versa
. Adjust R, or R, can be changed Light control point of the circuit .