Preliminary
FSTUD32211 40/48-Bit Bus Switch with -2V Undershoot Protection and Level Shifting (Preliminary)
February 2001
Revised August 2001
FSTUD32211
40/48-Bit Bus Switch with -2V Undershoot Protection
and Level Shifting (Preliminary)
General Description
The Fairchild Switch FSTUD32211 provides up to 48-bits
of high-speed CMOS TTL-compatible bus switching. The
low On Resistance of the switch allows inputs to be con-
nected to outputs without adding propagation delay or gen-
erating additional ground bounce noise. A diode to V
CC
has
been integrated into the circuit to allow for level shifting
between 5V inputs and 3.3V outputs.
The device can be organized as four 12-bit, two 24-bit, or
one 48-bit bus switch. When routed as a 40-bit bus switch,
the device can be organized as four 10-bit, two 20-bit or
one 40-bit bus switch. When OE
1
is LOW, the switch is ON
and Port 1A is connected to Port 1B. When OE
2
is LOW,
the switch is ON and Port 2A is connected to Port 2B.
When OE
3
is LOW, the switch is ON and Port 3A is con-
nected to Port 3B. When OE
4
is LOW, the switch is ON and
Port 4A is connected to Port 4B. When OE
1
, OE
2
, OE
3
, or
OE
4
are HIGH, a high impedance state exists between the
A and B Ports. The A and B Ports are protected against
undershoot to support an extended range to 2.0V below
ground. Fairchild鈥檚 integrated Undershoot Hardened Circuit
(UHC
錚?/div>
) senses undershoot at the I/O鈥檚, and responds by
preventing voltage differentials from developing and turn-
ing on the switch.
Features
s
Undershoot protected to
鈭?/div>
2V (A and B Ports)
s
Voltage level shifting
s
4
鈩?/div>
switch connection between two ports
s
Minimal propagation delay through the switch
s
Low l
CC
s
Zero bounce in flow-through mode
s
Control inputs compatible with TTL level
s
See Applications Notes AN-5008 and AN-5021 for UHC
details
s
Packaged in plastic Fine-Pitch Ball Grid Array
(FBGA) (Preliminary)
Ordering Code:
Order Number
FSTUD32211GX
(Note 1)
Package Number
BGA114A
(Preliminary)
Package Description
114-Ball Fine-Pitch Ball Grid Array (FBGA), JEDEC MO-205, 5.5mm Wide
[Tape and Reel]
Note 1:
BGA package available in Tape and Reel only.
漏 2001 Fairchild Semiconductor Corporation
DS500537
www.fairchildsemi.com
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