
Integrated Device Technology, Inc.
MILITARY AND COMMERCIAL TEMPERATURE RANGES
AUGUST 1995
1995 Integrated Device Technology, Inc.
6.9
DSC-4611/4
1
DESCRIPTION:
The IDT octal bidirectional transceivers are built using an
advanced dual metal CMOS technology. The FCT245T/
FCT2245T, FCT640T and FCT645T are designed for asyn-
chronous two-way communication between data buses. The
transmit/receive (T/
R
) input determines the direction of data
flow through the bidirectional transceiver. Transmit (active
HIGH) enables data from A ports to B ports, and receive
(active LOW) from B ports to A ports. The output enable (
OE
)
input, when HIGH, disables both A and B ports by placing
them in HIGH Z condition.
The FCT245T/FCT2245T and FCT645T transceivers have
non-inverting outputs. The FCT640T has inverting outputs.
The FCT2245T has balanced drive outputs with current
limiting resistors. This offers low ground bounce, minimal
for external series terminating resistors. The FCT2xxxT parts
are plug-in replacements for FCTxxxT parts.
FAST CMOS OCTAL
BIDIRECTIONAL
TRANSCEIVERS
IDT54/74FCT245T/AT/CT/DT - 2245T/AT/CT
IDT54/74FCT640T/AT/CT
IDT54/74FCT645T/AT/CT/DT
FEATURES:
Common features:
–
Low input and output leakage
≤
1
μ
A (max.)
–
CMOS power levels
–
True TTL input and output compatibility
– V
OH
= 3.3V (typ.)
– V
OL
= 0.3V (typ.)
–
Meets or exceeds JEDEC standard 18 specifications
–
Product available in Radiation Tolerant and Radiation
Enhanced versions
–
Military product compliant to MIL-STD-883, Class B
and DESC listed (dual marked)
–
Available in DIP, SOIC, SSOP, QSOP, CERPACK
and LCC packages
Features for FCT245T/FCT640T/FCT645T:
–
Std., A, C and D speed grades
–
High drive outputs (-15mA I
OH
, 64mA I
OL
)
Features for FCT2245T:
–
Std., A and C speed grades
–
Resistor outputs
(-15mA I
OH
, 12mA I
OL
Com.)
(-12mA I
OH
, 12mA I
OL
Mil.)
–
Reduced system switching noise
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PIN CONFIGURATIONS
FUNCTIONAL BLOCK DIAGRAM
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The IDT logo is a registered trademark of Integrated Device Technology, Inc.
LCC
TOP VIEW
5
6
7
8
9
10
A
1
A
2
A
3
A
4
A
5
A
6
A
7
1
2
3
4
20
19
18
17
16
15
14
13
12
11
Vcc
OE
B
0
T/R
A
0
B
1
B
2
B
3
B
4
B
5
B
6
B
7
GND
P20-1
D20-1
SO20-2
SO20-7*
SO20-8**
&
E20-1
INDEX
B
0
B
1
B
2
B
3
B
4
A
2
A
3
A
4
A
5
A
6
B
7
B
6
B
5
G
A
7
A
0
A
1
V
T
O
15
14
18
17
16
5
6
7
8
4
L20-2
9 10 11 12 13
3
2
1
20 19
*FCT245T/2245T, FCT645T only.
**FCT245T/2245T, FCT640T
DIP/SOIC/SSOP/QSOP/CERPACK
TOP VIEW
FCT245T/2245T, FCT645T are non-inverting options.
FCT640T is the inverting options.
A
B
0
0
T/R
OE
A
B
1
1
A
B
2
2
A
B
3
3
A
B
4
4
A
B
5
5
A
B
6
6
A
B
7
7
2539 drw 03