Three Digit Object Counter

Aim of this project is very simple it counts Objects or Pulses from IR proximity detector. Maximum count is 999. It can be reset at any point and pulses for counting can be given from various sensors, such as IR sensor or LDR circuit.

In this project we are using CD4033 consists of a 5 stage Johnson decade counter and an output decoder which converts the Johnson code to a 7-segment decoded output for driving one stage in a numerical display. This device is particularly advantageous in display applications where low power dissipation and/or low package count is important. A high RESET signal clears the decade counter to its zero count. The counter is advanced one count at the positive clock signal transition if the CLOCK INHIBIT signal is low. Counter advancement via the clock line is inhibited when the CLOCK INHIBIT signal is high. The CLOCK INHIBIT signal can be used as a negative-edge clock if the clock line is held high. Anti lock gating is provided on the JOHNSON counter, thus assuring proper counting sequence. The CARRY-OUT (Cout) signal completes one cycle every ten CLOCK INPUT cycles and is used to clock the succeeding decade directly in a multi-decade counting chain. The seven decoded outputs (a, b, c, d, e, f, g) illuminate the proper segments in a seven segment display device used for representing the decimal numbers 0 to 9. The 7 segment outputs go high on selection.

Component List

  1. CD4033  Qty. 3
  2. 7-Segment Display CC Qty.3
  3. 10K Resistors Qty. 2
  4. Tektile Switches Qty. 2

Object counter circuit tested in Proteus simulation

The circuit is consists of three common cathode displays, CD4033 counter/decode IC.


Object Counter Circuit
Object Counter Circuit

Eagle Circuit Diagram Used for PCB Development

Circuit Object Counter
Circuit Object Counter

Download Object Counter Circuit pdf

Eagle PCB Layout

We are using single sided PCB for designing of object counter. It is having two switches to give clock and reset the count. you can connect external sensor to clock in input. Give +5V power supply to the circuit. Red color lines are jumpers.

Object Counter PCB Layout
Object Counter PCB Layout

Download Object Counter Layout pdf

Develop this circuit and test with +5V. If you have any query please comment below. We have seen how to build simple Object counter. Now you can interface various proximity sensors to make it more practical.

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