The DM74LS15N is a triple 3-input AND gate with open-collector outputs belonging to the low-power Schottky (LS) TTL family of integrated circuits. Manufactured by National Semiconductor (now Texas Instruments), it is designed for applications requiring AND logic with the flexibility of wired-AND connections.

Applications:

• Wired-AND logic functions.
• Data selection and routing.
• Memory decoding.
• Control systems.
• Bus interface circuits.

Features:

• Triple 3-input AND gates.
• Low-power Schottky (LS) technology.
• Open-collector outputs.
• Operating voltage: 4.75V to 5.25V.
• Typical propagation delay of 15 ns.

Benefits:

• Wired-AND capability allows multiple outputs to be connected together to perform a logical AND function without additional gates.
• Low power consumption reduces overall system power requirements.
• Versatile logic function can be used in a wide range of digital applications.
• TTL compatibility ensures easy integration with other TTL logic devices.

Additional Details:

The DM74LS15N is available in a 14-pin DIP (Dual In-Line Package). The open-collector outputs require an external pull-up resistor to provide a HIGH logic level. When the output of the AND gate is HIGH (all inputs are HIGH), the output transistor is turned off, and the output voltage is pulled up to the supply voltage by the external resistor. When the output of the AND gate is LOW (any input is LOW), the output transistor is turned on, and the output voltage is pulled down to near ground. This allows multiple DM74LS15N outputs to be connected together; the resulting output will be LOW if any of the individual outputs are LOW, effectively performing a logical AND function of all the connected outputs.