The DM74ALS21AN is a quad AND gate from the Fairchild/ON Semiconductor 74ALS series of logic devices. It is designed for digital logic applications where logical AND operations are required. The gate has four inputs and provides a single output based on the logical AND of the inputs.

The DM74ALS21AN operates at a voltage supply range of 4.5V to 5.5V, making it compatible with standard logic levels. The propagation delay is specified as 15ns at a supply voltage of 5V and a load capacitance of 50pF. This means that the output of the gate will change within 15ns of a change in any of the inputs.

The DM74ALS21AN is packaged in a 14-DIP package, which is suitable for through-hole mounting. The operating temperature range is 0°C to 70°C, making it suitable for use in a wide range of environments.

Features:

• Quad AND gate
• Voltage supply range of 4.5V to 5.5V
• Propagation delay of 15ns at 5V
• 14-DIP package
• Operating temperature range of 0°C to 70°C

Applications:

• Digital logic circuits
• Arithmetic logic units (ALUs)
• Control circuits
• Memory address decoders
• Data bus buffers
• AND-OR-INVERT (AOI) circuits

Example circuit:

The following circuit shows how the DM74ALS21AN can be used to create a simple two-input AND gate:

In this circuit, the two inputs (A and B) are connected to two of the inputs of the DM74ALS21AN. The output of the DM74ALS21AN is connected to an LED.

When both inputs are HIGH, the output of the DM74ALS21AN will be HIGH, turning on the LED. When either input is LOW, the output of the DM74ALS21AN will be LOW, turning off the LED.

Conclusion:

The DM74ALS21AN is a versatile quad AND gate that can be used in a wide variety of digital logic applications. It is easy to use and has a small footprint, making it ideal for use in space-constrained applications.