CD74FCT646_14 Datasheet, PDF (3/12 Pages) Texas Instruments – BiCMOS OCTAL BUS TRANSCEIVER AND REGISTER WITH 3-STATE OUTPUTS

CD74FCT646
BiCMOS OCTAL BUS TRANSCEIVER AND REGISTER
WITH 3-STATE OUTPUTS
SCBS735A – JULY 2000 – REVISED JULY 2000
FUNCTION TABLE
INPUTS
DATA I/O
OE DIR CLKAB CLKBA SAB SBA
A1–A8
B1–B8
X
X
↑
X
X
X
Input
Unspecified†
X
X
X
↑
X
X Unspecified†
Input
OPERATION OR
FUNCTION
Store A, B unspecified†
Store B, A unspecified†
H
X
↑
↑
X
X
Input
Input
Store A and B data
H
X
H or L H or L
X
X Input disabled Input disabled Isolation, hold storage
L
L
X
X
X
L
Output
Input
Real-time B data to A bus
L
L
X
H or L
X
H
Output
Input
Stored B data to A bus
L
H
X
X
L
X
Input
Output
Real-time A data to B bus
L
H
H or L
X
H
X
Input
Output
Stored A data to B bus
† _{The data-output functions can be enabled or disabled by various signals at OE and DIR. Data-input functions always are}
enabled; i.e., data at the bus terminals is stored on every low-to-high transition of the clock inputs.
logic symbol^‡
21
OE
3
DIR
23
CLKBA
22
SBA
1
CLKAB
2
SAB
4
A1
5
A2
6
A3
7
A4
8
A5
9
A6
10
A7
11
A8
G3
3 EN1 [BA]
3 EN2 [AB]
C4
G5
C6
G7
≥1 5 ^4D
1
51
6D 7 ≥1
2
17
20
B1
19
B2
18
B3
17
B4
16
B5
15
B6
14
B7
13
B8
‡ _{This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.}
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