How to Build a Automatic PWM Door Open/Close Controller Circuit

The publish reveals a very simple PWM controlled automatic turnstile or door circuit presenting an automatic open/close action via a photo-interrupter stage.
A straightforward PWM based motor control circuit with high torque and immediate stop/reversal characteristic may be observed in the presented diagram and can be utilized for working the offered turnstile or automatic door application.

 


If an Arduino based PWM is meant to function, the IC phase in the above diagram could possibly be taken away and the PWM from the Arduino may very well be utilized instantly at the base of the mosfet via a 10 ohm resistor as demonstrated below

 


Parts List
R1 = 10K
R2 = 47 OHMS
P1 = 100K POT
D1, D2 = 1N4148
D3 = MUR1560
C1,C2 = 0.1uF/100V
Z1 = 15V, 1/2 WATT
Q1 = IRF540
N1—N6 = IC MM74C14
DPDT = DPST SWITCH OR DPDT RELAY
The to start with circuit above, which can be not making use of an Arduino input is set up around 6 hex-inverter Schmidt NOT gates from the IC MM74C14, where N1 forms the essential rectangular wave pulse generator, N2 is utilized for detecting the duty cycle of the pulses produced by N1 via the pot P1, although the remaining gates are wired as buffers.
P1 is employed for figuring out the speed exactly where the door ought to actually work instantly.
The ultimate PWM output accomplished from the outputs of the buffers N3 to N6 is put on to a driver mosfet Q1 which evolves into to blame for managing the speed of the connected motor based upon the given food PWM data.
A DPDT switch may be seen rigged with the motor terminals and the mosfet, this switch is utilized for getting an immediate braking and reversal of motor rotation.
The valuable thing concerning this circuit is the fact that it may rely on a H-bridge driver configuration for attaining the motor flipping actions, quite the identical is used through a regular DPDT switch.
According to the request, for performing the automatic door starting and shutting via photo delicate device, the DPDT might be replaced with a DPDT relay and the coil of this relay could possibly be consequently managed by means of the meant photo sensitive device (photo-interrupter) for example a photo diode or an LDR.
The photo interrupter level is going to be updated quickly.