© 2000 Fairchild Semiconductor Corporation

DS500319

www.fairchildsemi.com

March 2000

Revised March 2000

FST162861

20-Bit Bus Switch with 25

Ω Series Resistors in Outputs

General Description

The Fairchild Switch FST162861 provides 20-Bits of high-

speed CMOS TTL-compatible bus switching. The low on

resistance of the switch allows inputs to be connected to

outputs without adding propagation delay or generating

additional ground bounce noise.

The device is organized as a 10-bit or 20-Bit bus switch.

exists between the A and B ports. The FST162861 has an

equivalent 25

Ω series resistors to reduce signal-reflection

noise, eliminating the need for external terminating resis-

tors.

Features

s 25

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.

Ordering Code:

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

Connection Diagram

Pin Descriptions

Logic Diagram

Truth Table

Order Number

Package Number

Package Description

FST162861MTD

MTD48

48-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 6.1mm Wide

Pin Name

Description

Bus Switch Enables

1A, 2A

Bus A

1B, 2B

Bus B

Inputs

Inputs/Outputs

1A, 1B

2A, 2B

LL

1A

= 1B

2A

= 2B

LH

1A

= 1B

Z

HL

Z

2A

= 2B

HH

Z

Z