LTC4300A-3CMS8#PBF

Overview

The LTC4300A-3CMS8#PBF is a hot swappable 2-wire bus buffer manufactured by Analog Devices Inc. It supports bidirectional buffering for SDA and SCL lines, isolating backplane and card capacitances during live insertion. The device operates with supply voltages (VCC and VCC2) ranging from 2.7V to 5.5V. It features rise time accelerators that provide a typical transient boosted pull-up current of 2mA. The precharge voltage on SDA and SCL lines is typically 1V. The ENABLE pin threshold voltage ranges from 0.5•VCC to 0.9•VCC. The component is available in an 8-lead MSOP package and supports I2C, I2C Fast Mode, and SMBus standards up to 400kHz operation.

Feature Summary

• Provides bidirectional buffering while keeping backplane and card capacitances isolated
• Includes rise time accelerator circuitry to allow weaker DC pull-up currents
• Precharges SDA and SCL lines to 1V during insertion to minimize bus disturbances
• Features a CMOS threshold ENABLE pin for low current mode and isolation

Applications

• Hot board insertion into live backplanes
• Servers requiring I/O card insertion without data corruption
• Desktop computer systems utilizing I2C or SMBus interfaces

Procurement Notes

Verify the specific ordering suffix CMS8 corresponds to the MSOP package and commercial temperature range (0°C to 70°C). Confirm RoHS compliance status through official manufacturer documentation. Ensure the part number matches the exact functional requirements for 2-wire bus buffering applications.

Selection Notes

Select this component when designing systems requiring hot swapping capabilities for 2-wire buses. Ensure the system voltage falls within the 2.7V to 5.5V range for both VCC and VCC2. Consider the 8-lead MSOP package constraints for PCB layout. Verify that the bus capacitance and pull-up resistor values align with the rise time accelerator activation requirements.

Part Context

This part belongs to the LTC4300A series of hot swappable 2-wire bus buffers. It is functionally similar to the LTC4300A-1 and LTC4300A-2 but includes specific level translation and enable features. The CMS8 suffix indicates the MSOP package variant with a commercial operating temperature range, distinct from the industrial IMS8 variant.

Replacement Considerations

LTC4300A-1CMS8#PBF and LTC4300A-2CMS8#PBF are related parts in the same family. Verify functional compatibility regarding level shifting and enable logic before substitution.