Encyclopedia Entry: 74F251ASC

Product Overview

Category

The 74F251ASC belongs to the category of integrated circuits (ICs) and specifically falls under the family of multiplexers.

Use

This IC is primarily used for data selection and routing purposes in digital electronic systems. It allows multiple input signals to be selectively routed to a single output line, based on control inputs.

Characteristics

• The 74F251ASC is a high-speed, quad 2-input multiplexer.
• It operates on a supply voltage range of 4.5V to 5.5V.
• The IC is designed to work with TTL (Transistor-Transistor Logic) compatible inputs and outputs.
• It offers low power consumption and high noise immunity.
• The device is available in a small outline package (SOIC) with 16 pins.

Package and Quantity

The 74F251ASC is packaged in a standard SOIC package. Each package contains one IC.

Specifications

• Supply Voltage Range: 4.5V to 5.5V
• Input Voltage High (VIH): 2.0V (min)
• Input Voltage Low (VIL): 0.8V (max)
• Output Voltage High (VOH): 2.7V (min)
• Output Voltage Low (VOL): 0.5V (max)
• Operating Temperature Range: -40°C to +85°C

Pin Configuration

The 74F251ASC has a total of 16 pins, which are assigned specific functions as follows:

1. A0: Input A0
2. B0: Input B0
3. S0: Select Input S0
4. S1: Select Input S1
5. GND: Ground
6. Y: Output Y
7. A1: Input A1
8. B1: Input B1
9. S2: Select Input S2
10. S3: Select Input S3
11. VCC: Supply Voltage
12. Y: Output Y
13. A2: Input A2
14. B2: Input B2
15. S4: Select Input S4
16. S5: Select Input S5

Functional Features

• The 74F251ASC is a quad 2-input multiplexer, meaning it can select between four different input signals.
• The selection of inputs is controlled by the six select inputs (S0-S5).
• The selected input is routed to the output pin (Y) based on the control inputs.
• The IC operates at high speed, allowing for efficient data routing in digital systems.

Advantages and Disadvantages

Advantages

• High-speed operation enables quick data selection and routing.
• Low power consumption helps in reducing overall system energy requirements.
• TTL compatibility ensures easy integration with existing digital circuits.
• Small outline package (SOIC) allows for space-efficient PCB layout.

Disadvantages

• Limited to quad 2-input multiplexing functionality, may not be suitable for applications requiring higher input count.
• Operating temperature range may restrict usage in extreme environmental conditions.

Working Principles

The 74F251ASC works based on the principle of multiplexing. It uses the select inputs (S0-S5) to determine which input signal (A0-A2, B0-B2) is connected to the output pin (Y). The control inputs are decoded internally to activate the appropriate transmission gate, allowing the selected input to pass through to the output.

Application Field Plans

The 74F251ASC finds extensive use in various digital electronic systems, including but not limited to: - Data routing and selection in microprocessors and microcontrollers. - Address decoding in memory systems. - Input signal selection in communication devices. - Control signal routing in industrial automation systems.

Alternative Models

For users seeking alternative options, the following models can be considered: - 74HC251: A similar quad 2-input multiplexer with CMOS technology. - CD4053B: An analog multiplexer/demultiplexer IC with higher input count. - SN74LS157: A quad 2-line to 1-line data selector/multiplexer IC.

These alternatives offer different features and specifications, allowing users to choose based on their specific requirements.

---

Word Count: 530 words