Truth Tables
Inputs
Inputs
G1
(Note 1)
DIR1
A1(0–8)
B1(0–8)
G2
(Note 1)
DIR2
L
L
H←H
L
L
L
L
L←L
L
L
L
H
H→H
L
H
L
H
L→L
L
H
H
X
Z
Z
H
X
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance
Note 1: Inactive-to-Active transition must occur to enable outputs upon power-up.
A2(0–8)
B2(0–8)
H←H
L←L
H→H
L→L
Z
Z
Functional Description
The SCAN182245A consists of two sets of nine non-invert-
ing bidirectional buffers with 3-STATE outputs and is
intended for bus-oriented applications. Direction pins (DIR1
and DIR2) LOW enables data from B Ports to A Ports,
when HIGH enables data from A Ports to B Ports. The Out-
put Enable pins (G1 and G2) when HIGH disables both A
and B Ports by placing them in a high impedance condition.
Block Diagrams
A1, B1, G1 and DIR1
A2, B2, G2 and DIR2
Note: BSR stands for Boundary Scan Register.
Note: BSR stands for Boundary Scan Register.
Tap Controller
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