© 2005 Fairchild Semiconductor Corporation

DS500020

www.fairchildsemi.com

June 1997

Revised March 2005

FST3245

8-Bit Bus Switch

General Description

The Fairchild Switch FST3245 provides 8-bits of high-

speed CMOS TTL-compatible bus switching in a standard

’245 pin-out. The low on resistance of the switch allows

inputs to be connected to outputs without adding propaga-

tion delay or generating additional ground bounce noise.

The device is organized as an 8-bit switch. When OE is

LOW, the switch is ON and Port A is connected to Port B.

When OE is HIGH, the switch is OPEN and a high-imped-

ance state exists between the two ports.

Features

s 4

: 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.

Ordering Code:

Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.

Note 1: “_NL” indicates Pb-Free package (per JEDEC J-STD-020B). Device available in Tape and Reel only.

Logic Diagram

Pin Descriptions

Connection Diagram

Truth Table

Order Number

Package

Package Description

Number

FST3245WM

M20B

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide

FST3245QSC

MQA20

20-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150" Wide

FST3245MTC

MTC20

20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide

FST3245MTCX_NL

(Note 1)

MTC20

Pb-Free 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm

Wide

Pin Name

Description

OE

Bus Switch Enable

ABus A

BBus B

Input OE

Function

L

Connect

H

Disconnect