Encyclopedia Entry: 74AC245TTR

Product Overview

Category

The 74AC245TTR belongs to the category of integrated circuits (ICs), specifically a type of digital logic level shifter.

Use

This IC is commonly used for voltage level shifting in digital systems. It allows for bidirectional data transfer between devices operating at different voltage levels.

Characteristics

• Bidirectional voltage level shifting
• High-speed operation
• Low power consumption
• Wide operating voltage range
• Compatibility with various logic families

Package and Quantity

The 74AC245TTR is typically available in a small outline transistor (SOT) package. The package dimensions are standardized, allowing for easy integration into circuit boards. It is commonly sold in reels or tubes containing multiple units.

Essence

The essence of the 74AC245TTR lies in its ability to facilitate seamless communication between digital devices operating at different voltage levels, ensuring reliable data transfer.

Specifications

• Supply Voltage Range: 2V to 6V
• Logic Family: Advanced CMOS (AC)
• Number of Channels: 8
• Input/Output Compatibility: TTL/CMOS
• Maximum Data Rate: 200 MHz
• Operating Temperature Range: -40°C to +85°C

Detailed Pin Configuration

The 74AC245TTR features a dual in-line package (DIP) with 20 pins. The pin configuration is as follows:

1. OE (Output Enable) 1
2. A1 (Input/Output) 1
3. B1 (Input/Output) 1
4. A2 (Input/Output) 2
5. B2 (Input/Output) 2
6. A3 (Input/Output) 3
7. B3 (Input/Output) 3
8. GND (Ground)
9. B4 (Input/Output) 4
10. A4 (Input/Output) 4
11. B5 (Input/Output) 5
12. A5 (Input/Output) 5
13. B6 (Input/Output) 6
14. A6 (Input/Output) 6
15. B7 (Input/Output) 7
16. A7 (Input/Output) 7
17. B8 (Input/Output) 8
18. A8 (Input/Output) 8
19. VCC (Power Supply)
20. OE (Output Enable) 2

Functional Features

The key functional features of the 74AC245TTR include:

1. Bidirectional Data Transfer: The IC allows for data transfer in both directions, enabling seamless communication between devices operating at different voltage levels.
2. Voltage Level Shifting: It ensures compatibility between TTL and CMOS logic families by shifting the voltage levels appropriately.
3. High-Speed Operation: The IC operates at a high data rate of up to 200 MHz, making it suitable for applications requiring fast data transfer.
4. Output Enable Control: The output enable pins (OE) allow for easy control of data flow, enabling efficient power management.

Advantages and Disadvantages

Advantages

• Wide operating voltage range enables compatibility with various digital systems.
• High-speed operation facilitates fast data transfer.
• Low power consumption contributes to energy-efficient designs.
• Bidirectional data transfer simplifies circuit design and reduces component count.

Disadvantages

• Limited number of channels (8) may not be sufficient for complex systems requiring a higher channel count.
• Sensitivity to electrostatic discharge (ESD) requires proper handling during assembly and usage.

Working Principles

The 74AC245TTR operates based on the principles of voltage level shifting and bidirectional data transfer. It utilizes internal circuitry to convert input signals from one voltage level to another, ensuring compatibility between different logic families. The output enable pins allow for control over the direction of data flow.

Detailed Application Field Plans

The 74AC245TTR finds applications in various digital systems, including but not limited to:

1. Microcontrollers: Facilitating communication between microcontrollers operating at different voltage levels.
2. Communication Interfaces: Enabling data transfer between devices with varying logic levels, such as UART, SPI, or I2C interfaces.
3. Memory Systems: Supporting voltage level conversion between memory modules and controllers.
4. Industrial Automation: Providing level shifting capabilities in control systems and PLCs.
5. Consumer Electronics: Used in devices like smartphones, tablets, and gaming consoles for voltage level adaptation.

Alternative Models

For those seeking alternative options, several ICs offer similar functionality to the 74AC245TTR. Some notable alternatives include:

1. 74HCT245: A CMOS-based octal bus transceiver with similar voltage level shifting capabilities.
2. SN74LVCH