Overview
The SN74AXC4T245BQBR is a 4-bit dual-supply bus transceiver produced by Texas Instruments. This device is designed for asynchronous communication between two data buses and supports universal low-voltage bidirectional translation. It operates with a fully configurable dual-rail design, allowing each port to function over a wide power supply range from 0.65V to 3.6V. This makes it an excellent choice for translating between various low-voltage nodes such as 1.2V, 1.8V, 2.5V, and 3.3V.
Key Specifications
| Parameter | Min | Max | Unit |
|---|---|---|---|
| VCCA (Supply voltage A) | -0.5 | 4.2 | V |
| VCCB (Supply voltage B) | -0.5 | 4.2 | V |
| VI (Input voltage range) | -0.5 | 4.2 | V |
| VO (Output voltage range in high or low state) | -0.5 | VCCA + 0.2 / VCCB + 0.2 | V |
| TA (Operating free-air temperature) | -40 | 85 | °C |
| Continuous output current | -50 | 50 | mA |
| Input transition rise or fall rate | 5 | ns/V |
Key Features
- Fully configurable dual-rail design allowing each port to operate with a power supply range from 0.65V to 3.6V.
- Supports high-speed translation with data rates up to 380 Mbps for certain voltage transitions.
- Ioff feature supports partial-power-down mode operation, preventing backflow current by disabling I/O output circuits.
- VCC isolation feature ensures both I/O ports enter a high-impedance state if either VCCA or VCCB is less than 100mV.
- Glitch-free power supply sequencing allows either supply rail to be powered on or off in any order.
- Direction-control (DIR) and output-enable (OE) inputs control data transmission and output states.
Applications
- Low-voltage translation between different voltage nodes in mixed-voltage systems.
- Asynchronous communication between two data buses in various digital systems.
- High-speed data transmission applications requiring robust power sequencing and low-voltage operation.
- Partial-power-down mode applications where power conservation is critical.
Q & A
- What is the operating voltage range for the SN74AXC4T245BQBR?
The device operates with a power supply range from 0.65V to 3.6V for both VCCA and VCCB.
- What is the maximum data rate supported by the SN74AXC4T245BQBR?
The device can support data rates up to 380 Mbps for certain voltage transitions.
- How does the Ioff feature work in the SN74AXC4T245BQBR?
The Ioff feature prevents backflow current by disabling I/O output circuits when the device is in partial-power-down mode.
- What is the purpose of the VCC isolation feature?
The VCC isolation feature ensures both I/O ports enter a high-impedance state if either VCCA or VCCB is less than 100mV.
- How do the DIR and OE inputs control the device?
The DIR input controls the direction of data transmission, and the OE input enables or disables the output ports.
- What are the thermal characteristics of the SN74AXC4T245BQBR?
The device has various thermal metrics such as junction-to-ambient thermal resistance, junction-to-case thermal resistance, and junction-to-board thermal resistance, depending on the package type.
- What is the operating temperature range for the SN74AXC4T245BQBR?
The device operates over a temperature range from -40°C to 85°C.
- What are the package options available for the SN74AXC4T245BQBR?
The device is available in TSSOP, WQFN, and UQFN packages.
- How does the glitch-free power supply sequencing work?
The device allows either supply rail to be powered on or off in any order while providing robust power sequencing performance.
- What is the significance of holding unused data inputs at VCCI or GND?
Holding unused data inputs at VCCI or GND ensures proper device operation and prevents excess current consumption.
