LTC4313CDD-1#TRPBF

Signal Buffers, Repeaters, Splitters Overview

The LTC4313CDD-1#TRPBF is a hot swappable 2-wire bus buffer in an 8-lead (3mm × 3mm) plastic DFN package. It operates with a supply voltage range of 2.9V to 5.5V and supports I2C frequencies up to 400kHz. The device provides bidirectional buffering with a high noise margin defined by VIL = 0.3 • VCC. It includes rise time accelerators configured as slew-limited switches, capable of sourcing up to 40mA pull-up current. Input capacitance is typically 10pF, and the input supply current is 8.1mA at 5.5V. The operating temperature range is 0°C to 70°C.

Signal Buffers, Repeaters, Splitters Feature Summary

• Provides bidirectional buffering for 2-wire buses while maintaining high noise margins compatible with non-compliant devices driving high VOL levels.
• Features strong rise time accelerators that act as slew-limited switches to reduce bus rise times in heavily loaded systems.
• Includes precharge circuitry that forces SDA and SCL pins to 1V during insertion to minimize bus disturbances.
• Supports automatic stuck bus disconnect and recovery by generating clock pulses when both data and clock remain low.

Signal Buffers, Repeaters, Splitters Applications

• Bidirectional buffering to increase fanout on I2C and SMBus networks
• Live board insertion and removal from backplanes in telecommunications systems
• Level translation between 3.3V and 5V busses

Signal Buffers, Repeaters, Splitters Procurement Notes

Verify the specific ordering suffix #TRPBF confirms tape and reel packaging rather than tube. Confirm the C grade indicates the commercial temperature range of 0°C to 70°C. Ensure the DD-1 designation matches the required rise time accelerator configuration for the design.

Signal Buffers, Repeaters, Splitters Selection Notes

Select this variant over the -2 or -3 models if strong slew-limited switch rise time acceleration is required. The -1 model differs from the -2 which uses a fixed 2.5mA current source. Verify that the 40mA peak RTA capability aligns with the target bus capacitance and rise time specifications.

Signal Buffers, Repeaters, Splitters Part Context

This component belongs to the LTC4313 family of 2-wire bus buffers. The -1 suffix specifically denotes the version with strong rise time accelerators configured as slew-limited switches. Other variants include the -2 with constant current sources and the -3 supporting lower voltage level translation without RTAs.

Signal Buffers, Repeaters, Splitters Replacement Considerations

LTC4313CDD-1#PBF is the tube-packaged equivalent. LTC4313IDD-1#TRPBF offers the same electrical performance but with an extended industrial temperature range of –40°C to 85°C.

Signal Buffers, Repeaters, Splitters FAQ

How does the LTC4313-1 handle stuck bus conditions?

If both clock and data are not simultaneously high within 45ms, the device disconnects the input from the output and generates up to sixteen 5.5kHz clock pulses on the SCLOUT pin to attempt to free the stuck bus.

What is the function of the ENABLE pin?

Driving ENABLE low isolates the inputs from outputs and disables the rise time accelerators. Driving it high allows connection after a stop bit or bus idle condition is detected on both SDA and SCL lines.

Why is precharge used during live insertion?

The precharge circuit forces the SDA and SCL pins to a nominal 1V voltage before physical contact is fully established, minimizing disturbances to the active backplane bus during card insertion.