FST32253 Datasheet, PDF (1/5 Pages) Fairchild Semiconductor – Dual 4:1 Multiplexer/Demultiplexer Bus Switch with 25Ω Series Resistor in Outputs

August 2001
Revised September 2001
FST32253
Dual 4:1 Multiplexer/Demultiplexer Bus Switch
with 25Ω Series Resistor in Outputs
General Description
The Fairchild Switch FST32253 is a dual 4:1 high-speed
CMOS TTL-compatible multiplexer/demultiplexer bus
switch. The low On Resistance of the switch allows inputs
to be connected to outputs without adding propagation
delay or generating additional ground bounce noise.
When OE is LOW, S₀ and S₁ connect the A Port to the
selected B Port output. When OE is HIGH, the switch is
OPEN and a high-impedance state exists between the two
ports.
The FST32253 has an equivalent 25Ω series resistor to
reduce signal-reflection noise, eliminating the need for
external terminating resistors.
Features
s 25Ω 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
Ordering Code:
Order Number Package Number
Package Description
FST32253M
M16A
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150" Narrow
FST32253QSC
MQA16
16-Lead Quarter Size Outline Package (QSOP), JEDEC MO-137, 0.150" Wide
FST32253MTC
MTC16
16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.
Logic Diagram
Connection Diagram
Pin Descriptions
Pin Name
OE₁, OE₂
S₀, S₁
A
B₁, B₂, B₃, B₄
Description
Bus Switch Enables
Select Inputs
Bus A
Bus B
© 2001 Fairchild Semiconductor Corporation DS500472
Truth Table
S₁
S₀ OE₁ OE₂
X
X
H
X
X
X
X
H
L
L
L
L
L
H
L
L
H
L
L
L
H
H
L
L
Function
Disconnect 1A
Disconnect 2A
A = B₁
A = B₂
A = B₃
A = B₄
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