Sound and light controlled staircase delay switch circuit using op amp

It is a sound- and light-controlled delayed lighting switch for stairways and walkways made of I-V13 24 operational amplifiers.
It also uses a two-wire connection method, which directly replaces ordinary lighting switches without having to change the original wiring in the switch.
    VD3-VD6 and V_I constitute the main circuit of the delay light switch. The control loop is mainly composed of four operational amplifiers Al-A4
. For 220v AC power, choose VD3-VD6 rectifier, R. . Step-down, vs. voltage stabilization,
a stable DC voltage of about IOV can be obtained at both ends for Al-A-1 to use. Microphone B, A] and A2 form an acoustic circuit; Rl. Together with
A3, it forms a light-controlled electric hoof; R. , (1t constitutes the delay circuit after the lamp E is lit; LED is a light-emitting diode
used to indicate the switch position at night.
    During the day, RI is low power}fl, and the inverting input terminal ⑨ pin of A3 is high power +, so Pin ⑧ outputs low level, and
VD1 is turned on. At this time, no matter whether the voice control circuit has no input, it will clamp the non-inverting input terminal of A4, pin ⑥, to
low level , so the output of pin @ is low and the thyristor is flat. VT is always turned off and the lamp E will not light up. Only when it is late,
RI is high resistance, pin 8 of A3 is low level, pin 8 outputs high level, VD1 is reverse biased and cut off, thereby releasing the control
of A4. Block c. If someone is walking on the stairs at this time. H picks up the sound of people's footsteps, and is coupled to
the ③ pin of Al via (, so that the o pin outputs a high level, and then coupled to the ⑤ pin of A2 via (1. The ⑦ pin of A2 outputs a high
level. This high level
turns on VDZ, which is added to
the input terminal of ^{.
The ⑩ pin outputs a high level,
the 66 thyristor VT is opened, and the light
E is on. . "_J is positive lu source
through V L2 to (1. Find|乜.
After the sound, the ⑦ pin of A2
returns to low level, VD2 is cut
off, but the G stored I charge can
be slowly discharged through R, and
continues to maintain the @ pin Keep
the level high, so the light will not go out immediately. About:/0s C, when the voltage at both ends, that is, the level of the @ pin is lower than the level of the ⑥ pin, the
@ pin returns to low voltage, and the transistor YT loses the trigger current . When the no-current lU crosses zero, and u is turned off and the light F is turned off.
    In the figure, the operating circuit Al-Al connected to four voltage comparators can use a single power supply four operational amplifier integrated circuit
LM32-1. Other J[devices See the picture for parameters, especially special requirements.