Overview
The SN74ACT245PWG4 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 operates within a VCC range of 4.5V to 5.5V and is compatible with TTL-voltage inputs. The SN74ACT245PWG4 is available in a TSSOP (Thin Shrink Small Outline Package) with 20 pins, making it suitable for a variety of applications where bus interface and signal integrity are crucial.
Key Specifications
| Parameter | Unit | Min | Typ | Max |
|---|---|---|---|---|
| VCC Supply Voltage | V | 4.5 | 5.5 | |
| VIH High-level Input Voltage | V | 2 | 2 | |
| VIL Low-level Input Voltage | V | 0.8 | 0.8 | |
| TA Operating Free-air Temperature | °C | -40 | 85 | |
| tPLH Propagation Delay Time (A to B or B to A) | ns | 1 | 4 | 7.5 |
| tPHL Propagation Delay Time (A to B or B to A) | ns | 1 | 4 | 8 |
| IOH High-level Output Current | mA | -24 | ||
| IOL Low-level Output Current | mA | 24 | ||
| RθJA Junction-to-ambient Thermal Resistance (TSSOP) | °C/W | 126.6 |
Key Features
- Operates within a VCC range of 4.5V to 5.5V
- Inputs accept voltages up to 5.5V
- Maximum propagation delay time of 8ns at 5V
- TTL-voltage compatible inputs
- Low drive and slow edge rates to minimize output ringing
- 3-state outputs for bus isolation
- Available in TSSOP package with 20 pins
Applications
- Pro Audio systems
- Video and Signage systems
- Appliances
- Factory Automation and Control systems
- Bus interface applications where output ringing is a concern
Q & A
- What is the operating voltage range of the SN74ACT245PWG4?
The SN74ACT245PWG4 operates within a VCC range of 4.5V to 5.5V.
- What is the maximum propagation delay time of the SN74ACT245PWG4 at 5V?
The maximum propagation delay time is 8ns at 5V.
- Are the inputs of the SN74ACT245PWG4 TTL-voltage compatible?
- What package type is the SN74ACT245PWG4 available in?
The SN74ACT245PWG4 is available in a TSSOP (Thin Shrink Small Outline Package) with 20 pins.
- What is the purpose of the output enable (OE) pin?
The output enable (OE) pin controls the state of the outputs. When OE is low, the device passes noninverted data between the A and B buses. When OE is high, the device is in a high-impedance state, isolating the buses.
- What is the recommended power supply configuration for the SN74ACT245PWG4?
Each VCC pin should have a good bypass capacitor to prevent power disturbance. A 0.1 μF capacitor is recommended for single VCC pins, and multiple bypass capacitors can be used in parallel for better noise rejection.
- What are the thermal considerations for the SN74ACT245PWG4?
The junction-to-ambient thermal resistance (RθJA) for the TSSOP package is 126.6 °C/W. Proper thermal management is essential to ensure reliable operation.
- What are some common applications of the SN74ACT245PWG4?
The SN74ACT245PWG4 is commonly used in Pro Audio, Video and Signage, Appliances, and Factory Automation and Control systems.
- How does the SN74ACT245PWG4 minimize output ringing?
The device has low drive and slow edge rates, which help minimize overshoot and undershoot on the outputs, reducing output ringing.
- What is the operating temperature range of the SN74ACT245PWG4?
The operating free-air temperature range is -40°C to 85°C.
