PCA9510A_1

© Koninklijke Philips Electronics N.V. 2005. All rights reserved.

Product data sheet

Rev. 01 — 8 September 2005

8 of 23

Philips Semiconductors

PCA9510A

8.8 Hot swapping and capacitance buffering application

Figure 7 through Figure 10 illustrate the usage of the PCA9510A in applications that take

advantage of both its hot swapping and capacitance buffering features. In all of these

applications, note that if the I/O cards were plugged directly into the backplane, all of the

backplane and card capacitances would add directly together, making rise time and

fall time requirements difficult to meet. Placing a bus buffer on the edge of each card,

however, isolates the card capacitance from the backplane. For a given I/O card, the

PCA9510A drives the capacitance of everything on the card and the backplane must drive

only the capacitance of the bus buffer, which is less than 10 pF, the connector, trace, and

all additional cards on the backplane.

See

Application Note AN10160, ‘Hot Swap Bus Buffer’ for more information on

applications and technical assistance.

Fig 5.

Bus requirements for 3.3 V systems

Fig 6.

Bus requirements for 5 V systems

0

400

300

100

200

002aab582

10

20

30

(k

Ω)

0

recommended

pull-up

rise time > 300 ns

0

400

300

100

200

002aab583

10

5

15

20

(k

Ω)

0

recommended

pull-up

rise time > 300 ns