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
undershoot and controlled output fall times- reducing the need
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