Overview
The SN74ACT245DW is an octal bus transceiver with 3-state outputs, manufactured by Texas Instruments. This device is designed for asynchronous two-way communication between data buses, making it suitable for a variety of applications where data transfer between different bus systems is required. The SN74ACT245DW operates within a VCC range of 4.5V to 5.5V and is compatible with TTL voltage levels, ensuring seamless integration into existing systems.
Key Specifications
| Parameter | Min | Max | Unit |
|---|---|---|---|
| VCC Supply Voltage | 4.5 | 5.5 | V |
| VIH High-level Input Voltage | 2 | 2 | V |
| VIL Low-level Input Voltage | 0.8 | 0.8 | V |
| IOH High-level Output Current | -24 | -24 | mA |
| IOL Low-level Output Current | 24 | 24 | mA |
| tPLH Propagation Delay (A to B or B to A) | 1 | 9 | ns |
| tPHL Propagation Delay (A to B or B to A) | 1 | 10 | ns |
| TA Operating Free-Air Temperature | -40 | 85 | °C |
Key Features
- Operates within a VCC range of 4.5V to 5.5V, making it compatible with 5V systems.
- Inputs accept voltages up to 5.5V, ensuring compatibility with TTL voltage levels.
- Maximum propagation delay of 8ns at 5V, providing high-speed data transfer.
- 3-state outputs allow for bus isolation when the output-enable (OE) is high.
- Low drive and slow edge rates minimize output ringing and overshoot.
- Available in various packages including SOIC (DW), SSOP (DB), TSSOP (PW), and others.
Applications
- Professional Audio Systems: For reliable data transfer in audio equipment.
- Video and Signage: Used in video processing and display systems.
- Appliances: Integrated into various consumer and industrial appliances for data communication.
- Factory Automation and Control: Utilized in industrial control systems for efficient data exchange.
Q & A
- What is the operating voltage range of the SN74ACT245DW?
The SN74ACT245DW operates within a VCC range of 4.5V to 5.5V.
- What is the maximum propagation delay of the SN74ACT245DW at 5V?
The maximum propagation delay is 8ns at 5V.
- How do the 3-state outputs function in the SN74ACT245DW?
The 3-state outputs allow for bus isolation when the output-enable (OE) is high.
- What are the typical applications of the SN74ACT245DW?
It is used in professional audio systems, video and signage, appliances, and factory automation and control.
- What are the available package types for the SN74ACT245DW?
Available packages include SOIC (DW), SSOP (DB), TSSOP (PW), and others.
- How should the output-enable (OE) be managed during power-up or power-down?
The OE should be tied to VCC through a pullup resistor to ensure the high-impedance state.
- What is the recommended bypass capacitor for the power supply?
A 0.1 μF capacitor is recommended, and it can be paralleled with a 1 μF capacitor for better noise rejection.
- What is the significance of the direction-control (DIR) input in the SN74ACT245DW?
The DIR input determines the direction of data transfer between the A and B buses.
- How does the SN74ACT245DW minimize external timing requirements?
The control-function implementation minimizes external timing requirements, making it suitable for asynchronous two-way communication.
- What are the thermal characteristics of the SN74ACT245DW?
The junction-to-ambient thermal resistance varies by package, e.g., 98.6 °C/W for SOIC (DW) package.
