Powered by Blogger.

Wednesday 29 October 2014

Working of Circuit - Seven Segment Display + 7490 + 4511 + Press Button Switch (Part 2)

by realfinetime  |  in Seven Segment Display at  20:46

<<<<  Read Previous Part (Part 1)

Pin out diagram of 4511

          Datasheet of 4511 is given here. Datasheet must be read before using 4511. 4511 is a BCD to 7-segment latch / decoder / driver with four address inputs (D0-D3), an active low blanking input (BL), a lamp test (LT) and a latch enable (LE).

          From the function table of 4511 given in page 2 of datasheet, it is clear that, when a BCD input is given to 4511 through D0, D1, D2 and D3, we will get a corresponding number displayed in seven segment display. BCD input for 4511 is given from the output pins of 7490 (Qa, Qb, Qc and Qd). LT and BL pins of 4511 should be at HIGH voltage. Similarly LE pin should be at LOW voltage.

Pin out diagram of Common Cathode Seven Segment Display

          Pin out diagram of common cathode seven segment display is given below. There will be only one cathode pin for all the eight anode pins. Segments of the seven segment display is connected to the output pins (Qa - Qg) of 4511. A resistor of 1 K should be connected to the anode pins to protect the segments from high currents.
          Vcc is given from a regulated 5V source. Vcc is given to 7490 as well as 4511. Gnd pin of 7490, 4511 and Common cathode seven segment display is connected to the Gnd pin of voltage source.

Working of Circuit

          When the press button switch is pressed, 7490 will increment the counter and BCD corresponding to the present count will be there at the output pins (Qa, Qb, Qc and Qd) of 7490. This BCD output is given as input to the 4511 IC. Number corresponding to the BCD given as input to the 4511 will be displayed at the seven segment display. In the next press of press button switch, count will increment again and the number displayed at the seven segment display get incremented. After 9, count will restart from 0 again.

Next : Watch the Video Demonstration >>>>



All the circuits, published in this blog is only after testing and getting proper results in my private lab. When you try these circuits, you should check the supply voltage, polarity of components, presence of childrens nearby and shorts in the circuits. This website will not be responsible for any harm happened to you or your components caused by your carelessness.

For More Electronic Tips

Blog Archive

Proudly Powered by Blogger.