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SN74LS688N
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SN74LS688N

Product Overview

  • Category: Integrated Circuit (IC)
  • Use: Comparator
  • Characteristics: 8-bit Magnitude Comparator
  • Package: DIP (Dual In-line Package)
  • Essence: High-speed TTL logic comparator
  • Packaging/Quantity: Tube packaging, 25 pieces per tube

Specifications

  • Supply Voltage: 4.75V to 5.25V
  • Input Voltage: 0V to Vcc
  • Operating Temperature Range: 0°C to 70°C
  • Output Current: ±4mA
  • Propagation Delay Time: 15ns (typical)
  • Power Dissipation: 500mW (max)

Detailed Pin Configuration

The SN74LS688N has a total of 20 pins. Here is the detailed pin configuration:

  1. A0 - Input A0
  2. A1 - Input A1
  3. A2 - Input A2
  4. A3 - Input A3
  5. A4 - Input A4
  6. A5 - Input A5
  7. A6 - Input A6
  8. A7 - Input A7
  9. B0 - Input B0
  10. B1 - Input B1
  11. B2 - Input B2
  12. B3 - Input B3
  13. B4 - Input B4
  14. B5 - Input B5
  15. B6 - Input B6
  16. B7 - Input B7
  17. G - Enable Input
  18. EQ - Output Equality Indicator
  19. LT - Output Less Than Indicator
  20. GT - Output Greater Than Indicator

Functional Features

  • Performs 8-bit magnitude comparison between two binary numbers.
  • Outputs three signals indicating equality, less than, and greater than conditions.
  • Supports high-speed TTL logic operation.
  • Provides reliable and accurate comparison results.

Advantages and Disadvantages

Advantages: - High-speed operation allows for quick comparison of large binary numbers. - Accurate comparison results ensure reliable decision-making in digital systems. - Wide operating temperature range makes it suitable for various environments.

Disadvantages: - Limited to 8-bit magnitude comparison, not suitable for larger bit sizes. - Requires external enable signal for operation.

Working Principles

The SN74LS688N compares two 8-bit binary numbers (A and B) by examining each corresponding bit. It determines whether A is equal to, less than, or greater than B. The result is indicated by the EQ, LT, and GT outputs. The enable input (G) controls the comparison process. When G is high, the comparison is enabled, and the outputs reflect the comparison result.

Detailed Application Field Plans

The SN74LS688N is commonly used in various applications, including:

  1. Digital arithmetic circuits
  2. Data processing systems
  3. Microcontrollers
  4. Control units
  5. Communication devices

Detailed and Complete Alternative Models

Here are some alternative models that can be used as replacements for the SN74LS688N:

  1. SN74LS682
  2. SN74LS684
  3. SN74LS686
  4. SN74LS689

These alternatives offer similar functionality and can be used interchangeably depending on specific requirements.

In conclusion, the SN74LS688N is a high-speed TTL logic comparator used for 8-bit magnitude comparison. It provides reliable and accurate results, making it suitable for various digital systems. With its wide application field and availability of alternative models, it offers flexibility in design and implementation.

10個與SN74LS688N在技術方案中應用相關的常見問題與解答

Sure! Here are 10 common questions and answers related to the application of SN74LS688N:

  1. Q: What is SN74LS688N? A: SN74LS688N is a 8-bit magnitude comparator IC (integrated circuit) commonly used in digital electronics.

  2. Q: What is the purpose of a magnitude comparator? A: A magnitude comparator compares two binary numbers and determines their relative magnitudes (greater than, less than, or equal).

  3. Q: What are the key features of SN74LS688N? A: SN74LS688N has 8 inputs for comparing two 8-bit numbers, outputs indicating the comparison result, and additional control inputs for various operations.

  4. Q: How can SN74LS688N be used in technical solutions? A: It can be used in applications such as arithmetic logic units (ALUs), data processing systems, digital calculators, and other circuits requiring number comparison.

  5. Q: How do I connect SN74LS688N in my circuit? A: Connect the two 8-bit numbers to be compared to the A and B inputs respectively. Provide appropriate power supply and ground connections.

  6. Q: What are the output pins of SN74LS688N used for? A: The output pins provide the comparison results, such as greater than, less than, or equal, which can be used for further processing or decision-making.

  7. Q: Can SN74LS688N handle negative numbers? A: No, SN74LS688N is designed to compare unsigned binary numbers. It does not handle negative numbers directly.

  8. Q: What is the maximum operating frequency of SN74LS688N? A: The maximum operating frequency of SN74LS688N is typically around 25 MHz, but it can vary depending on the specific conditions and circuit design.

  9. Q: Can SN74LS688N be cascaded to compare larger numbers? A: Yes, multiple SN74LS688N ICs can be cascaded together to compare larger numbers by connecting the carry output of one comparator to the carry input of the next.

  10. Q: Are there any precautions or considerations when using SN74LS688N? A: It is important to ensure proper power supply voltage, avoid exceeding maximum ratings, and follow recommended operating conditions as specified in the datasheet.