?/DIV>
4301 supply independent, hot swappable, 2-wire
bus buffer allows I/O card insertion into a live backplane
without corruption of the data and clock busses. In addi-
tion, the LTC4301 allows the V
CC
, SDAIN and SCLIN pull-
up voltage and the SDAOUT and SCLOUT pull-up voltage
to be independent from each other. Control circuitry
prevents the backplane from being connected to the card
until a stop bit or a bus idle is present. When the connec-
tion is made, the LTC4301 provides bidirectional buffer-
ing, keeping the backplane and card capacitances isolated.
During insertion, the SDA and SCL lines are precharged to
1V to minimize bus disturbances. When driven low, the CS
input pin allows the part to connect after a stop bit or bus
idle occurs. Driving CS high breaks the connection be-
tween SCLIN and SCLOUT and between SDAIN and
SDAOUT. The READY output pin indicates that the back-
plane and card sides are connected together.
The LTC4301 is offered in 8-pin DFN (3mm ?3mm) and
MSOP packages.
10k
10k
5V
BACK_SCL
BACKPLANE
CONNECTOR
CARD
BACK_SDA
3.3V
10k
5V
CS
CARD_SCL
CARD_SDA
SCLOUT
SCLIN
SDAOUT
SDAIN
GND
V
CC
LTC4301
READY
0.01礔
4301 TA01
10k    10k
Input-Output Connection
4301 TA01b
OUTPUT
SIDE
20pF
INPUT
SIDE
55pF
1祍/DIV
1V/DIV
, 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.