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74AC257TTR
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Encyclopedia Entry: 74AC257TTR

Product Overview

Category

The 74AC257TTR belongs to the category of integrated circuits (ICs).

Use

This IC is commonly used in digital electronics for data multiplexing applications.

Characteristics

  • The 74AC257TTR is a quad 2-input multiplexer with 3-state outputs.
  • It operates on a supply voltage range of 2V to 6V.
  • This IC offers high-speed operation and low power consumption.
  • It has a wide operating temperature range, making it suitable for various environments.

Package

The 74AC257TTR is available in a small-outline transistor (SOT) package.

Essence

The essence of the 74AC257TTR lies in its ability to select one of four data inputs and route it to a single output line.

Packaging/Quantity

This IC is typically sold in reels or tubes, containing a specific quantity per package. Please refer to the manufacturer's specifications for detailed packaging information.

Specifications

  • Supply Voltage Range: 2V to 6V
  • Input Voltage Range: 0V to VCC
  • Output Voltage Range: 0V to VCC
  • Operating Temperature Range: -40°C to +85°C
  • Maximum Propagation Delay: 7 ns
  • Maximum Power Dissipation: 500 mW

Detailed Pin Configuration

The 74AC257TTR has a total of 16 pins, each serving a specific function:

  1. A0: Data Input A0
  2. B0: Data Input B0
  3. A1: Data Input A1
  4. B1: Data Input B1
  5. GND: Ground
  6. Y: Multiplexer Output
  7. E: Enable Input
  8. C: Data Input C
  9. D: Data Input D
  10. B2: Data Input B2
  11. A2: Data Input A2
  12. VCC: Supply Voltage
  13. Y3: 3-State Output Y3
  14. Y2: 3-State Output Y2
  15. Y1: 3-State Output Y1
  16. Y0: 3-State Output Y0

Functional Features

The 74AC257TTR offers the following functional features:

  • Quad 2-input multiplexer with 3-state outputs.
  • Selects one of four data inputs based on control signals.
  • Provides a single output line for the selected input.
  • Enables or disables the output using the enable input.

Advantages and Disadvantages

Advantages

  • High-speed operation allows for efficient data multiplexing.
  • Low power consumption helps conserve energy.
  • Wide operating temperature range ensures versatility in various environments.

Disadvantages

  • Limited to quad 2-input multiplexing applications.
  • Requires careful handling due to its small size and delicate pins.

Working Principles

The 74AC257TTR operates by receiving four data inputs (A, B, C, D) and selecting one of them based on the control signals (A0, A1, A2). The selected input is then routed to the output pin (Y). The enable input (E) controls whether the output is enabled or disabled. When disabled, the output enters a high-impedance state, allowing other devices to drive the output line.

Detailed Application Field Plans

The 74AC257TTR finds application in various digital systems, including but not limited to: - Multiplexing data from multiple sources into a single output line. - Address decoding in microprocessors and memory systems. - Data routing in communication systems. - Signal selection in audio and video equipment.

Detailed and Complete Alternative Models

There are several alternative models available in the market that offer similar functionality to the 74AC257TTR. Some notable alternatives include: - 74HC257: A CMOS version of the IC with similar characteristics. - CD4051: An analog multiplexer/demultiplexer IC with additional features. - SN74LS157: A TTL logic quad 2-line to 1-line data selector/multiplexer.

Please refer to the manufacturer's specifications for a comprehensive list of alternative models.

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Noem 10 veelgestelde vragen en antwoorden met betrekking tot de toepassing van 74AC257TTR in technische oplossingen

Sure! Here are 10 common questions and answers related to the application of 74AC257TTR in technical solutions:

  1. Q: What is the 74AC257TTR? A: The 74AC257TTR is a quad 2-input multiplexer with 3-state outputs, commonly used in digital logic circuits.

  2. Q: What is the purpose of a multiplexer? A: A multiplexer is used to select one of several input signals and route it to a single output line.

  3. Q: How many inputs does the 74AC257TTR have? A: The 74AC257TTR has four inputs, labeled A0, A1, A2, and A3.

  4. Q: Can the 74AC257TTR handle both analog and digital signals? A: No, the 74AC257TTR is designed for digital signals only.

  5. Q: How many output lines does the 74AC257TTR have? A: The 74AC257TTR has four output lines, labeled Y0, Y1, Y2, and Y3.

  6. Q: What is the maximum voltage that the 74AC257TTR can handle? A: The 74AC257TTR can handle a maximum voltage of 5.5V.

  7. Q: Can the 74AC257TTR be cascaded to increase the number of inputs? A: Yes, multiple 74AC257TTRs can be cascaded together to increase the number of inputs.

  8. Q: Does the 74AC257TTR have any built-in protection features? A: Yes, the 74AC257TTR has built-in ESD protection on all inputs and outputs.

  9. Q: What is the power supply voltage range for the 74AC257TTR? A: The 74AC257TTR operates with a power supply voltage range of 2V to 5.5V.

  10. Q: Can the outputs of the 74AC257TTR be put into a high-impedance state? A: Yes, the 74AC257TTR has 3-state outputs that can be put into a high-impedance state using the enable input (E).