8

LTC4301

4301fb

APPLICATIO S I FOR ATIO

they make contact. CS is a short pin that is pulled up when

not connected. This is to ensure that the connection

between the backplane and the cards data and clock

busses is not enabled until the transients associated with

live insertion have settled.

Figure 4 shows the LTC4301 in a CompactPCI

the long “early power” pins. Because this power is not

switched, add a 5

present at SDAIN and SCLIN before they make contact.

The CS pin is driven by the CompactPCI’s BD_SEL# pin

using a short pin. This is to ensure that a connection is not

enabled until the transients associated with live insertion

have settled.

Figure 5 shows the LTC4301 in a PCI application where all

of the pins have the same length. In this case, an RC filter

circuit on the I/O card with a product of 10ms provides a

R13

10k

R12

10k

R14

10k

I/O PERIPHERAL CARD N

SDAIN

SCLIN

LTC4301

GND

CARDN_SCL

CARDN_SDA

SDAOUT

SCLOUT

READY

SDAIN

SCLIN

GND

SDAOUT

SCLOUT

READY

CS

SDAIN

SCLIN

GND

SDAOUT

SCLOUT

READY

4301 F03

R9

10k

R8

10k

R10

10k

I/O PERIPHERAL CARD 2

LTC4301

CARD2_SCL

CARD2_SDA

R5

10k

R4

10k

R6

10k

I/O PERIPHERAL CARD 1

LTC4301

CARD_SCL

CARD_SDA

R1

10k

R2

10k

BACKPLANE

BACKPLANE

CONNECTOR

SDA

BD_SEL

SCL

0.01

µF

R3

10k

5.1

Ω

5.1

Ω

5.1

Ω

R7

10k

R11

10k

0.01

µF

0.01

µF

CS

CS

Figure 4. Inserting Multiple I/O Cards into a Live Backplane Using the LTC4301 in a CompactPCI System

CompactPCI is a trademark of the PCI Industrial Computer Manufacturers Group.