Overview
The SN74ALS245A-1DW 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, minimizing external timing requirements. It allows data transmission from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the device, effectively isolating the buses.
Key Specifications
| Parameter | Unit | MIN | NOM | MAX |
|---|---|---|---|---|
| Supply Voltage (VCC) | V | 4.5 | 5 | 5.5 |
| High-Level Input Voltage (VIH) | V | 2 | 2 | 2 |
| Low-Level Input Voltage (VIL) | V | 0.7 | 0.8 | 0.8 |
| High-Level Output Current (IOH) | mA | -12 | -15 | -15 |
| Low-Level Output Current (IOL) | mA | 12 | 24 | 48† |
| Operating Free-Air Temperature (TA) | °C | 0 | - | 70 |
| Propagation Delay Time (tPLH, tPHL) | ns | 1 | - | 19 |
| Output Enable Time (tPZH, tPZL) | ns | 2 | - | 30 |
Key Features
- Octal bus transceiver with 3-state outputs for bidirectional data transmission.
- Direction-control (DIR) input to select the direction of data transmission.
- Output-enable (OE) input to disable the device and isolate the buses.
- High output drive capability: up to 48 mA for the -1 version.
- Low power consumption.
- Operating temperature range: 0°C to 70°C.
- Available in various packages, including SOIC, SOP, and SSOP.
Applications
- Data transmission and reception in microprocessor systems.
- Bus interfacing and isolation in digital systems.
- Peripheral device communication.
- Industrial control systems.
- Embedded systems requiring bidirectional data communication.
Q & A
- What is the primary function of the SN74ALS245A-1DW?
The primary function is to facilitate bidirectional data transmission between two data buses (A and B) with 3-state outputs.
- How is the direction of data transmission controlled?
The direction is controlled by the logic level at the direction-control (DIR) input.
- What is the purpose of the output-enable (OE) input?
The OE input is used to disable the device, effectively isolating the buses.
- What is the maximum low-level output current for the -1 version?
The maximum low-level output current for the -1 version is 48 mA.
- What is the operating temperature range for this device?
The operating temperature range is 0°C to 70°C.
- In what packages is the SN74ALS245A-1DW available?
It is available in SOIC, SOP, and SSOP packages.
- What are some common applications for this device?
Common applications include data transmission and reception in microprocessor systems, bus interfacing, peripheral device communication, and industrial control systems.
- What are the recommended operating conditions for VCC?
The recommended operating conditions for VCC are 4.5 V to 5.5 V.
- What are the propagation delay times for this device?
The propagation delay times (tPLH, tPHL) range from 1 ns to 19 ns.
- How do you ensure proper device operation for unused inputs?
All unused inputs must be held at VCC or GND to ensure proper device operation.
