LTC4300A-3

Features n Bidirectional Buffer* for SDA and SCL Lines Increases Fanout n Prevents SDA and SCL Corruption During Live Board Insertion and Removal From Backplane n Logic Threshold ENABLE Input n Isolates Input SDA and SCL Lines From Output n Compatible with I2C, I2C Fast Mode and SMBus Standards (Up to 400kHz Operation) n 1V Precharge on all SDA and SCL Lines n Supports Clock Stretching, Arbitration and Synchronization ■ 5V to 3.3V Level Translation ■ High Impedance SDA, SCL Pins for VCC = 0V, VCC2 = 0V ■ Small 8-Lead DFN and MSOP Packages Applications n Hot Board Insertion n Servers n Capacitance Buffer/Bus Extender n Desktop Computer LTC4300A-3 Level-Shifting Hot Swappable 2-Wire Bus Buffer with Enable Description The LTC®4300A-3 hot swappable 2-wire bus buffer allows I/O card insertion into a live backplane without corruption of the data and clock busses. When the connection is made, the LTC4300A-3 provides bidirectional buffering, keeping the backplane and card capacitances isolated. Rise time accelerator circuitry allows the use of weaker DC pull-up currents while still meeting rise time requirements. During insertion, the SDA and SCL lines are precharged to 1V to minimize bus disturbances. The LTC4300A-3 provides level translation between 3.3V and 5V supplies. The backplane and card can both be powered with supplies ranging from 2.7V to 5.5V. The LTC4300A-3 also incorporates a CMOS threshold ENABLE pin which forces the part into a low current mode and isolates the card ...