Overview
The TCA4311A, produced by Texas Instruments, is a hot-swappable I2C bus buffer designed to support the insertion of I/O cards into a live backplane without corrupting the data and clock buses. This device ensures seamless communication between the backplane and the card by providing bidirectional buffering and isolating the capacitances of the backplane and card. It operates with Standard Mode and Fast Mode I2C devices, as well as SMBus devices, and is equipped with features such as 1-V precharge on SDA and SCL lines to minimize current during insertion and removal. The TCA4311A also includes an open-drain READY output pin to indicate when the backplane and card sides are connected.
Key Specifications
| Parameter | Min | Max | Unit |
|---|---|---|---|
| Supply Voltage (VCC) | 2.7 | 5.5 | V |
| Operating Temperature Range | -40 | 85 | °C |
| High-Level Input Voltage (VIH) | 2 | 5.5 | V |
| Low-Level Input Voltage (VIL) | -0.5 | 0.4 | V |
| Low-Level Output Current (IOL) | 3 | 3 | mA |
| Package Type | VSSOP (8 pins) | ||
| Package Size | 3.00 mm × 3.00 mm |
Key Features
- Operating power-supply voltage range of 2.7 V to 5.5 V
- Supports bidirectional data transfer of I2C bus signals
- SDA and SCL lines are buffered, increasing fanout
- 1-V precharge on all SDA and SCL lines to prevent corruption during live board insertion and removal
- SDA and SCL input lines are isolated from outputs
- Accommodates Standard Mode and Fast Mode I2C devices, as well as SMBus devices
- Improved noise immunity
- Low ICC chip disable of < 1 μA
- READY open-drain output pin
- Supports clock stretching, arbitration, and synchronization
- Powered-off high-impedance I2C pins
- Open-drain I2C pins
- Latch-up performance exceeds 100 mA per JESD 78, Class II
- ESD protection exceeds JESD 22: 8000-V Human-Body Model, 200-V Machine Model, 1000-V Charged-Device Model
Applications
- Servers
- Routers (Telecom Switching Equipment)
- Base Stations
- Industrial Automation
- Hot board insertion and bus extension
Q & A
- What is the primary function of the TCA4311A?
The TCA4311A is a hot-swappable I2C bus buffer designed to support the insertion of I/O cards into a live backplane without corrupting the data and clock buses.
- What voltage range does the TCA4311A operate within?
The TCA4311A operates within a supply voltage range of 2.7 V to 5.5 V.
- What types of I2C devices does the TCA4311A support?
The TCA4311A supports Standard Mode, Fast Mode I2C devices, and SMBus devices.
- How does the TCA4311A prevent data corruption during insertion?
The TCA4311A prevents data corruption by pre-charging the SDA and SCL lines to 1 V and isolating the backplane and card capacitances.
- What is the purpose of the READY output pin?
The READY output pin indicates when the backplane and card sides are connected.
- How can the TCA4311A be put into shutdown mode?
The TCA4311A can be put into shutdown mode by setting the EN pin low.
- What is the significance of the rise-time accelerators in the TCA4311A?
The rise-time accelerators allow the use of weaker pull-up resistors by providing additional current during positive bus transitions to meet system rise-time requirements.
- What kind of ESD protection does the TCA4311A offer?
The TCA4311A offers ESD protection exceeding JESD 22: 8000-V Human-Body Model, 200-V Machine Model, and 1000-V Charged-Device Model.
- What is the thermal operating range of the TCA4311A?
The TCA4311A operates within an operating free-air temperature range of -40°C to 85°C.
- What is the package type and size of the TCA4311ADGKR?
The TCA4311ADGKR comes in a VSSOP (8 pins) package with a size of 3.00 mm × 3.00 mm.
