74LS90 Decade Counter IC (7490 IC)

The 74LS90 is a 4-bit decade counter integrated circuit, commonly known as the 7490 IC, designed for counting and frequency division applications in digital electronic systems. It is widely used in timing, counting, and digital display applications due to its flexible internal structure and reliable operation.

The IC consists of two internal counter sections: a divide-by-2 stage and a divide-by-5 stage. These sections can be combined to form a divide-by-10 (decade) counter, which counts from 0 to 9 in Binary Coded Decimal (BCD) format. By reconfiguring the internal connections, the 74LS90 can also be used to implement other counting modes such as bi-quinary, modulo-12, and modulo-16 counters, making it highly versatile for various digital design requirements.

The 74LS90 belongs to the Low Power Schottky TTL (LS TTL) family, offering fast switching speeds and low power consumption. It operates with a standard 5V power supply and is compatible with other TTL logic devices. Its asynchronous (ripple) counting design allows it to efficiently handle pulse counting and frequency division tasks.

This IC is commonly used in digital clocks, event counters, frequency dividers, timers, and display systems where accurate counting of pulses is required. Its reliability, flexibility, and ease of use make it a popular choice in both educational and industrial electronics.

Features

• 4-bit decade (BCD) counter IC

• Internal divide-by-2 and divide-by-5 counter stages

• Configurable for modulo-10, modulo-12, modulo-16, and other counters

• Low Power Schottky TTL (LS TTL) technology

• Standard 5V operating voltage

• High-speed switching performance

• Low power consumption

• Asynchronous ripple counter design

• TTL compatible inputs and outputs

• Reliable and stable operation

• Compact 14-pin DIP package

Applications

• Digital clocks and timers

• Frequency divider circuits

• Event and pulse counters

• Digital display systems

• Industrial automation systems

• Embedded electronics projects

• Measurement instruments

• Sequence generation circuits

• Educational electronics experiments

• Robotics and control systems