SMH4042A
using a QuickSwitch® from Quality Semiconductor. This
I/O Buffers
Depending upon the application requirements there are a particular device exhibits very Flat RON characteristics
number of silicon solutions that employ low on-resistance from 0 to 5V. The only drawback is the extra space
CMOS switches. Figure 15 shows one implementation required for the external pull-up resistors.
Early Power
SMH4042A
–
+
1V
REF
LMV321
SGNL_VLD#
OE#
Bn
Bx
An
Ax
IDTQS34XVH245
2070 Fig15
Figure 15. Bus Buffers with External Pull-ups
Figure 16 shows another implementation, but the pull-up edge of the card. The board designer should evaluate
resistor structure is incorporated in the switch. The requirements and design goals to determine the best
circuit also automatically switches the bias voltage out of solution. The bus switches are available from both Texas
thecircuitastheCMOSswitchesareenabled. Apotential Instruments and Pericom Semiconductor.
advantage is the ability to place the interface closer to the
Early Power
SMH4042A
–
+
1V
REF
LMV321
SGNL_VLD#
BIASV
ON#
Bn
Bx
An
Ax
SN74CBT6800
or PI5C6800
2070 Fig16
Figure 16. Bus Buffers with Integrated Pull-ups
SUMMIT MICROELECTRONICS, Inc.
2070 9.1 5/27/03
19