2- & 4-Channel Hot Swap I2C Multiplexers Provide Capacitive Buffering

The LTC4312 and LTC4314 are suitable for a wide range of applications, including radial architectures in telecommunications systems such as ATCA, address expansion and level translators. Many I2C and SMBus devices operate at different supply voltage levels, yet must communicate in the same application. The LTC4312 and LTC4314 support level translation for bus voltages ranging from 1.5V to 5.5V, providing the ability to power devices from different supply voltages while maintaining fully bidirectional communications between all devices in the system. Bidirectional buffering keeps backplane and card capacitances isolated, while maintaining low offsets and high noise margins up to 0.3VCC. In addition, built-in rise time accelerators provide strong pull-up currents on SCL and SDA rising edges to meet I2C rise time specifications for heavily loaded busses; the strength of these accelerators can be selected or disabled completely. Safety measures include a stuck bus disconnect and recovery feature to disengage the input from all enabled output channels and issue clocks to the stuck device, a fault output to signal when the host a bus is stuck low, and ±4kV HBM ESD protection for increased ruggedness.

The LTC4312 is available in 14-lead 4mm x 3mm DFN and 16-lead SSOP packages, and the LTC4314 is available in 20-lead 3mm x 4mm QFN and 20-lead SSOP packages.