Preliminary

© 2001 Fairchild Semiconductor Corporation

DS500537

www.fairchildsemi.com

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-

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

the switch is ON and Port 2A is connected to Port 2B.

A and B Ports. The A and B Ports are protected against

undershoot to support an extended range to 2.0V below

ground. Fairchild’s integrated Undershoot Hardened Circuit

(UHC

) senses undershoot at the I/O’s, and responds by

preventing voltage differentials from developing and turn-

ing on the switch.

Features

s Undershoot protected to

−2V (A and B Ports)

s Voltage level shifting

s 4

Ω switch connection between two ports

s Minimal propagation delay through the switch

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:

Note 1: BGA package available in Tape and Reel only.

Order Number

Package Number

Package Description

FSTUD32211GX

(Note 1)

BGA114A

(Preliminary)

114-Ball Fine-Pitch Ball Grid Array (FBGA), JEDEC MO-205, 5.5mm Wide

[Tape and Reel]