LTC4312IMS#TRPBF

Signal Buffers, Repeaters, Splitters Overview

The LTC4312IMS#TRPBF is a hot-swappable, pin-selectable 2-channel 2-wire bus multiplexer with bidirectional buffering. It supports I²C, SMBus, and PMBus protocols across multiple voltage domains including 1.5V, 1.8V, 2.5V, 3.3V, and 5V. The device operates within an input supply range of 2.9V to 5.5V and features selectable rise time accelerators controlled by the ACC pin. It provides high noise margin (VIL = 0.3•VCC) and includes automatic stuck bus disconnect and recovery logic that generates up to 16 clock pulses upon fault detection. Packaged in a 16-lead MSOP.

Signal Buffers, Repeaters, Splitters Feature Summary

• Bidirectional buffering isolates upstream bus capacitance from downstream loads while supporting level translation between various bus voltages.
• Hot-swap capability prevents data corruption during live board insertion or removal from backplanes.
• Automatic stuck bus detection and recovery mechanism disconnects faulty buses and attempts to free them using generated clock pulses.

Signal Buffers, Repeaters, Splitters Applications

• Telecommunications systems including ATCA
• I²C address expansion
• Level translation between different voltage domains
• Capacitance buffering and bus extension
• Live board insertion applications

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the specific ordering suffix #TRPBF confirms tape and reel packaging rather than tube. Confirm the IMS designation corresponds to the industrial temperature range (-40°C to 85°C). Ensure compatibility with the required 16-lead MSOP footprint for PCB layout.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this component when a 1:2 multiplexing function with independent channel enable control is required. Consider the VCC2 supply requirement if output-side rise time acceleration is necessary. Verify that the total bus current does not exceed the 4mA sink capability when multiple channels are active simultaneously.

Signal Buffers, Repeaters, Splitters Part Context

This part belongs to the LTC4312 family of 2-wire bus multiplexers. The IMS variant specifically denotes the 16-lead plastic MSOP package option. Other variants include DFN packages and commercial temperature grades, offering flexibility for different thermal and spatial constraints.

Signal Buffers, Repeaters, Splitters Replacement Considerations

LTC4312IMS#PBF is the tube version of the same functional device. Cross-reference with other Analog Devices bus buffers like the LTC4313 for higher noise margin requirements or LTC4312CDE#TRPBF for commercial temperature ranges.

Signal Buffers, Repeaters, Splitters FAQ

How does the ACC pin affect the rise time accelerator?

The ACC pin controls the turn-on voltage and current strength of the rise time accelerators. Grounding ACC enables strong acceleration, leaving it open enables a 3mA constant current source mode, and tying it high disables the accelerators.

What happens when a stuck bus condition is detected?

If DISCEN is high, the device disconnects the input and output sides and generates up to sixteen clock pulses on the enabled downstream busses to attempt recovery. A FAULT signal is pulled low to indicate the condition.

Can the LTC4312 be cascaded with other bus buffers?

Yes, multiple LTC4312 devices can be cascaded with each other or with other LTC bus buffers. Designers must account for additive logic low offset voltages to ensure sufficient noise margins across the cascade.