The 74HCT257D from NXP Semiconductors is a high-speed Si-gate CMOS device that is pin compatible with low-power Schottky TTL (LSTTL). It is specified in compliance with JEDEC standard no. 7A. This integrated circuit is part of the 74HCT family, which is known for its high noise immunity and low power consumption.

The 74HCT257D is a versatile multiplexer featuring four independent 2-input multiplexers with 3-state outputs. It is designed to select 4 bits of data from two sources under the control of a common data select input (S). The data is presented at the outputs in non-inverted form. An additional output enable input (OE) is provided to control the 3-state outputs. When OE is low, the outputs are active and reflect the data selected. When OE is high, the outputs are in a high-impedance state, effectively disconnecting them from the rest of the circuit which allows for bus sharing.

This multiplexer operates on a +5V power supply and offers a broad operating temperature range from -40°C to +125°C, making it suitable for a wide range of applications in the industrial, commercial, and telecommunications sectors. The 74HCT257D is available in a 16-pin SO package, ensuring a compact footprint for space-constrained applications.

Key features of the 74HCT257D include:

• High noise immunity
• Low power dissipation
• Typical t<sub>pd of 8 ns
• Output capability: bus driver
• ICC category: MSI

Applications for the 74HCT257D are diverse and include:

• Function generators
• Digital signal processing
• Data routing
• Computer peripheral multiplexing
• Control systems

The 74HCT257D embodies the quality and reliability that NXP Semiconductors is known for, making it an excellent choice for designers looking for a multiplexer with high functional integrity and performance across a broad range of operating conditions.