LTC4300A-1IMS8#PBF

Overview

The LTC4300A-1IMS8#PBF is a hot swappable 2-wire bus buffer designed for I/O card insertion into live backplanes without data corruption. It provides bidirectional buffering for SDA and SCL lines, isolating backplane and card capacitances while supporting I2C, Fast Mode, and SMBus standards up to 400kHz. The device features rise-time accelerator circuitry that allows the use of weaker DC pull-up currents while meeting rise-time requirements. During insertion, SDA and SCL lines are precharged to 1V to minimize bus disturbances. The part includes a CMOS threshold digital ENABLE input pin for low current shutdown mode and an open drain READY output pin indicating connection status. It operates with supply voltages from 2.7V to 5.5V.

Feature Summary

• Hot swappable 2-wire bus buffers allow I/O card insertion into a live backplane without corruption of the data and clock busses
• Rise-time accelerator circuitry allows the use of weaker DC pull-up currents while still meeting rise-time requirements
• SDA and SCL lines are precharged to 1V during insertion to minimize bus disturbances
• CMOS threshold digital ENABLE input pin forces the part into a low current mode when driven to ground

Applications

• Bidirectional Buffer for SDA and SCL Lines Increases Fanout
• Prevents SDA and SCL Corruption During Live Board Insertion and Removal from Backplane
• Isolates Input SDA and SCL Lines from Output
• Compatible with I2C, I2C Fast Mode and SMBus Standards (Up to 400kHz Operation)
• Low ICC Chip Disable: <1μA (LTC4300A-1)

Procurement Notes

Verify the specific suffix IMS8 indicates industrial temperature range (-40°C to +85°C) and MSOP-8 package. Confirm PBF denotes lead-free finish. Check datasheet for exact ordering codes and availability through authorized Analog Devices distributors. Ensure compatibility with system voltage levels and bus capacitance requirements before procurement.

Selection Notes

Select this component for applications requiring hot swapping of I/O cards into live backplanes. It is suitable for systems needing isolation between backplane and card capacitances while maintaining signal integrity on I2C or SMBus lines. Consider the ENABLE pin functionality for power management and the READY output for connection status monitoring in complex bus architectures.

Part Context

The LTC4300A series includes variants like the LTC4300A-2 which replaces the ENABLE pin with a dedicated VCC2 supply pin for level shifting between 3.3V and 5V systems. The IMS8 suffix specifically denotes the industrial temperature range and MSOP-8 package format. This part belongs to the broader family of hot swappable bus buffers designed for robust communication in server and desktop computer environments.

Replacement Considerations

Public confirmed substitute part numbers include LTC4300A-1CMS8#TRPBF for tape and reel packaging or LTC4300A-1IMS8#TRPBF for industrial temperature range tape and reel. Direct replacements within the same package and temperature range should be verified against the latest datasheet for pin compatibility and electrical characteristics.