Display System used in Restaurant

Now a day's self service system is available in most of the restaurants that informs the customer about the status of their order. A display system is used to show their order numbers on the screen. The circuit is easy to assemble. Its a simple technology,whenever a order is ready chef presses the switch and the number is displayed on board that informs customers to collect their order. The system removes the excessive crowd at the counter and save customers from unnecessary confusion. The circuit displays the numbers till 99, than again reset the counter. Therefore order numbers are used from 0 to 99. This circuit is based on 4026 IC which is a Johnson counter IC commonly used in digital display. It can be used in various application like in 7 segment decimal display circuit, in clocks, timer etc.

This circuit is based on 4026 IC which is a Johnson counter IC commonly used in digital display. It can be used in various application like in 7 segment decimal display circuit, in clocks, timer etc. Advantage of 4026 counter–

1. It contain counter and 7 segment decoding in one package.

2. It can be easily interface with 7 segment types.

3. Ideal for low power display.

4. Operated at wide range of temperature from 5V to 20V.

5. The big advantage of the 4026 counter IC is that it can drive a 7-segment display without needing a decoder driver IC

Working of the restaurant display circuit–

Whenever a customer places a order, a token number is given to them. Later when the number is displayed on screen (7 segment display), the customer can collect their order. Assemble the circuit properly. Connect the pin 3 of both the IC 1 and 2 to supply, to on the display. If pin 3 is connected to ground we will get a blank display on 7 segment output. Also connect the pin 15 which is a reset pin, to the ground so that when counting reaches to 99 it will reset the counter to zero automatically when switch is pressed. Also connect the pin 2 that is disable clock (clk inhibit) to ground. As 4026 counter advances one by one by receiving positive pulse, for this clock inhibit pin should be grounded. If it is connected to supply than counter advancement will be inhibited means there will be no meaning of clock pulse.

Now apply power supply. Zero will be displayed on both the 7 segment display. As soon as first order is ready, chef will press the switch. This will provide a clock pulse to pin 1 (which is a clock input pin) of IC1. After receiving the clock pulse 4026 IC counter advances and 1 will be displayed on common cathode 7 segment display. When second customer enters and same phenomenon occurs till count reaches 9. When it reaches 9 one cycle is completed. As you can see from circuit diagram pin 5 of IC1 is connected to pin 1 of IC2 to cascade another IC, after every 10th pulse it will go high to provide a clock pulse to IC2 to advance its counter that’s why we will receive a 1 on 7 segment common cathode display 2. In this unit place number are displayed on display 1 and tens place numbers are displayed on display 2. After completion of each cycle tens place advances one. Similarly you can add N numbers of 4026 IC with 7 segment display.