LTC4307

1

4307f

Low Offset Hot Swappable

2-Wire Bus Buffer with Stuck

Bus Recovery

I/O card insertion into a live backplane without corrup-

tion of the data and clock busses. The LTC4307 provides

bidirectional buffering, keeping the backplane and card

allows multiple devices to be cascaded on the clock and

data busses. If SDAOUT or SCLOUT are low for 30ms, the

LTC4307 will automatically break the bus connection. At

this time the LTC4307 automatically generates up to 16

clock pulses on SCLOUT in an attempt to free the bus. A

connection will resume if the stuck bus is cleared.

During insertion, the SDA and SCL lines are pre-charged

to 1V to minimize bus disturbances. When driven high,

the ENABLE input allows the LTC4307 to connect after a

stop bit or bus idle. Driving ENABLE low breaks the con-

nection between SDAIN and SDAOUT, SCLIN and SCLOUT.

READY is an open-drain output which indicates that the

backplane and card sides are connected.

Board Insertion and Removal from Backplane

× 3mm) DFN and 8-Lead MSOP

Packages

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

3.3V

ENABLE

10k

LTC4307

SCLIN

SDAIN

SCLOUT

SDAOUT

READY

GND

BACKPLANE

CONNECTOR

10k

2.7k

10k

10k

0.01

μF

CARD_SCL

CARD_SDA

10k

100k

3.3V

ENABLE

LTC4307

SCLIN

SDAIN

SCLOUT

SDAOUT

READY

GND

CARD

10k

4307 TA01a

3.3V

2.7k

MICRO-

CONTROLLER

CARD

CONNECTOR

0.01

μF

100ns/DIV

0

0

100

200

300

400

600

500

200

400

600

800

1000

4307 TA01b

SDAOUT

SDAIN

LOW

OFFSET

Rising Edge from Asserted Low

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

Protected by U.S. Patents, including 7032051, 6356140, 6650174