LTC4308

6

4308f

ENABLE (Pin 1): Connection Enable Input. This 0.6V nomi-

nal threshold input pin enables or disables the LTC4308.

For normal operation, pull or connect ENABLE high. Driving

ENABLE below the 0.45V threshold isolates SDAIN from

SDAOUT, SCLIN from SCLOUT, asserts READY low, and

prohibits automatic clock and stop bit generation during a

fault condition. A rising edge on ENABLE after a fault has

occurred forces a connection between SDAIN, SDAOUT

SCLOUT (Pin 2): Serial Clock Output. Connect this pin to a

SCL bus segment where bus stuck low recovery is desired.

A pull-up resistor should be connected between this pin

SCLIN (Pin 3): Serial Clock Input. Connect this pin to a SCL

bus segment where isolation from bus stuck low issues is

desired. A pull-up resistor should be connected between

this pin and a bus pull-up supply greater than 0.9V.

GND (Pin 4): Device Ground. Connect this pin to a ground

plane for best results.

READY (Pin 5): Connection Ready Status Output. This

open-drain N-channel MOSFET pin pulls low when

ENABLE is low, when the startup and connection sequence

described in the Operation section has not been completed,

or when the LTC4308 disconnects the input and output

pins due to a bus stuck low condition. READY goes high

when ENABLE is high and connection is made between the

input and output pins. Connect a pull-up resistor, typically

10k, from this pin to the bus pull-up supply. This pin can

be left open if unused.

SDAIN (Pin 6): Serial Data Input. Connect this pin to a SDA

bus segment where isolation from bus stuck low issues is

desired. A pull-up resistor should be connected between

this pin and a bus pull-up supply greater than 0.9V.

SDAOUT (Pin 7): Serial Data Output. Connect this pin to a

SDA bus segment where bus stuck low recovery is desired.

A pull-up resistor should be connected between this pin

Exposed Pad (Pin 9, DFN Package Only): Exposed Pad

may be left open or connected to device ground.

PIN FUNCTIONS