Decimal counter consisting of 74LS290

Photocoupler

Below is the circuit diagram for a decimal counter built using the 74LS290.

The 74LS290 is a versatile integrated circuit that can be configured as a decade counter, which means it counts from 0 to 9 before resetting.

Table 12.5 shows the state transfer table for this counter configuration:

This IC is widely used in digital circuits due to its simplicity and reliability. It can be cascaded with other counters to create more complex counting systems. For instance, by connecting multiple 74LS290 chips together, you can build a binary-coded decimal (BCD) counter or even a modulus counter, depending on your application needs. Additionally, the 74LS290 supports asynchronous reset and preset functions, making it highly flexible for various applications such as frequency dividers, timers, and shift registers.

Overall, the 74LS290 remains an essential component in modern electronics, offering engineers and hobbyists alike a straightforward way to implement basic counting operations within their designs.