Compination code circuit without Ardiunue nor ICs for Door Interlock

[Abughaith]

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 Door interlock combination code key

<span;>Electronic Circuit Description:
<span;>1- Password Keys (4 digits) = 1 7 9 #
<span;>2- Reset = 0
<span;>3- Other keys (false inputs )= partially circuit reset and discharging through resistor+Red LED.
<span;>4- Mosfet Transistor Q1 (IRF540) to operate a relay.
<span;>6- 12VDC Relay or 6VDC according to the Supply Voltage (VDD).

<span;>Note:
<span;>- keys ( 3 and *) are NC. not connected
<span;>- Circuit Supply Voltage from 6 to 12 VAC or DC.
<span;>- load lED indicator is optional with very small Resistance.
<span;>- Reset LED for discharging the capacitor not for indicating purpose only.
<span;>- Control any load by connecting the relay terminals (Com+NO).

<span;>Disgined & Implemented by :
<span;>ENG. Mustafa Hamoud Alghaithy
<span;>22 / 4 / 2021
<span;>mustafa.ghaithy@gmail.com