Circuit explanation for the ultrasonic alarm


Posted on Feb 5, 2014

The alarm detector circuit is different from Ultrasonic Alarm (1). In Ultrasonic Alarm (1), an alarm output is presented when there is a reflected wave from the object in the setup time. At the circuit this time, an alarm is output when no reflected wave from the object is detected in the setup time oppositely. The existence of the reflected wave


Circuit explanation for the ultrasonic alarm
Click here to download the full size of the above Circuit.

in the setup time is detected like Ultrasonic Alarm (1) to do this operation. As for the time setting for 555 timer and so on, please refer to Alarm detector of Ultrasonic Alarm (1). The initialization of the circuit is done with transmission timing pulse (A). C to "L", D and F to "H", G to "L" by which D goes to "H". When a reflected wave is detected within the setup time of 555 timer, C goes to "H". With this, the E shifts to "L". When the E goes "L", F shifts "L" and it is held until the next initialization. G shifts to "H" when D goes "L" with the time-out of 555 timer. However, because F is "L", the alarm output H is held on "H" and an alarm signal isn`t output. The initialization of the circuit is done with transmission timing pulse (A). C to "L", D and F to "H", G to "L" by which D goes to "H". When a reflected wave isn`t detected within the setup time of 555 timer, the change of the E doesn`t occur. It is held on "H". When D goes to "L" by the time-out of 555 timer, G shifts to "H". Because F is held on "H", H shifts to "L" and an alarm signal is output. Even if a reflected wave is detected behind the time-out of 555 timer, because D is held on "L" already, the change of the condition of E doesn`t occur. It is held on "H". So, the alarm output is kept. Alarm detecting circuit is composed of SR-FF (The set and reset type flip-flop circuit) and 555 timer. The reset of SR-FF for alarm detecting which is composed of IC8...




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Headlight circuit
    One-chip radar detection circuit
    Laser Power Supply
    Simple 2 Transistor Headphone Amplifier
    Simple Proximity Detector & Alarm Circuit
    scr high power alarm driver circuit design
    1999 Jeep Grand Cherokee Gauges shutoff
    led dimmer circuit
    Adjustable regulator using L200
    Si3210 Si3211 Si3212 Hardware Reference Guide
    smart phone light circuit diagram
    255W Valve RF Transmitter circuit



    Top