Decimal counter consisting of 74LS290

Photocoupler

The following is the circuit diagram of a decimal counter composed of the 74LS290.

The 74LS290 is a versatile integrated circuit that can be configured as a decimal counter. It is widely used in digital circuits for counting and frequency division purposes. Below is its circuit diagram:

Table 12.5 shows the state transfer table for this decimal counter. This table illustrates how the outputs change with each clock pulse, making it easier to understand the operation of the counter.

In summary, the 74LS290 is a simple yet effective component for building digital counters. Its ability to function as a modulus-2, modulus-5, or modulus-10 counter makes it a popular choice among hobbyists and professionals alike. Whether you're designing a clock, a frequency divider, or any other digital system, the 74LS290 can be a valuable addition to your toolkit.