54FCT245 Octal Bidirectional Transceiver with TRI-STATE Outputs
August 1998
54FCT245
Octal Bidirectional Transceiver with TRI-STATE
®
Outputs
General Description
The ’FCT245 contains eight non-inverting bidirectional buff-
ers with TRI-STATE outputs and is intended for bus-oriented
applications. Current sinking capability is 48 mA on both the
A and B ports. The Transmit/Receive (T/R) input determines
the direction of data flow through the bidirectional trans-
ceiver. Transmit (active HIGH) enables data from A ports to B
ports; Receive (active LOW) enables data from B ports to A
ports. The Output Enable input, when HIGH, disables both A
and B ports by placing them in a High Z condition.
Features
n
TTL input and output level compatible
n
A and B output sink capability of 48 mA, source
capability of 12 mA
n
CMOS power consumption
n
Standard Microcircuit Drawing (SMD) 5962-8762901
Ordering Code:
Military
54FCT245DMQB
54FCT245FMQB
54FCT245LMQB
Package
Number
J20A
W20A
E20A
20-Lead Ceramic Dual-In-Line
20-Lead Cerpak
20-Lead Ceramic Leadless Chip Carrier, Type C
Package Description
Logic Symbol
DS100950-1
TRI-STATE
®
is a registered trademark of National Semiconductor Corporation.
© 1998 National Semiconductor Corporation
DS100950
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Connection Diagrams
Pin Assignment for DIP
and Flatpak.
Pin Assignment for LCC
DS100950-3
DS100950-5
Pin Descriptions
Pin Names
OE
T/R
A
0
–A
7
B
0
–B
7
Description
Output Enable Input (Active LOW)
Transmit/Receive Input
Side A Inputs or TRI-STATE Outputs
Side B Inputs or TRI-STATE Outputs
Truth Table
Inputs
OE
L
L
H
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Output
T/R
L
H
X
Bus B Data to Bus A
Bus A Data to Bus B
High Z State
Logic Diagram
DS100950-4
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2
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature
Ambient Temperature under Bias
Junction Temperature under Bias
Ceramic
V
CC
Pin Potential to
Ground Pin
Input Voltage (Note 2)
Input Current (Note 2)
Voltage Applied to Any Output
in the Disabled or
Power-off State
−65˚C to +150˚C
−55˚C to +125˚C
−55˚C to +175˚C
−0.5V to +7.0V
−0.5V to +7.0V
−30 mA to +5.0 mA
in the HIGH State
Current Applied to Output
in LOW State (Max)
−0.5V to V
CC
twice the rated I
OL
(mA)
Recommended Operating
Conditions
Free Air Ambient Temperature
Military
Supply Voltage
Military
−55˚C to +125˚C
+4.5V to +5.5V
Note 1:
Absolute maximum ratings are values beyond which the device may
be damaged or have its useful life impaired. Functional operation under these
conditions is not implied.
Note 2:
Either voltage limit or current limit is sufficient to protect inputs.
−0.5V to 5.5V
DC Electrical Characteristics
Symbol
V
IH
V
IL
V
CD
V
OH
V
OL
I
IH
I
BVIT
I
IL
I
OS
I
CCQ
∆I
CC
I
CCT
Parameter
Min
Input HIGH Voltage
Input LOW Voltage
Input Clamp Diode Voltage
Output HIGH
Voltage
Output LOW
Voltage
54FCT
54FCT
54FCT
54FCT
4.3
2.4
0.2
0.55
5
5
Input HIGH Current Breakdown Test
(I/O)
Input LOW Current
Output Short-Circuit Current
Power Supply Current
Power Supply Current
Total Power Supply Current
6.0
mA
20
−5
−60
1.5
2.0
2.0
0.8
−1.2
FCT245
Max
Units
V
V
V
V
V
V
V
µA
µA
µA
mA
mA
mA
Min
Min
Min
Min
Min
Max
Max
Max
Max
Max
Max
V
CC
Conditions
Recognized HIGH Signal
Recognized LOW Signal
I
IN
= −18 mA (OE, T/R)
I
OH
= −300 uA (A
n
, B
n
)
I
OH
= −12 mA (A
n
, B
n
)
I
OL
= 300 uA (A
n
, B
n
)
I
OL
= 48 mA (A
n
, B
n
)
V
IN
= 2.7V (OE, T/R)
V
IN
= V
CC
(OE, T/R)
V
IN
= 5.5V (A
n
, B
n
)
V
IN
= 0.0V (OE, T/R)
V
OUT
= 0.0V (A
n
, B
n
)
V
IN
= 0.2V or V
IN
= 5.3V, V
CC
=
5.5V
V
CC
= 5.5V, V
IN
= 3.4V
V
IN
= 3.4V or V
IN
= GND, OE =
T/R = GND, V
CC
= 5.5V, f
I
=
10Mhz, outputs open, one bit
toggling - 50% duty cycle
V
IN
= 5.3V or V
IN
= 0.2V,OE =
T/R = GND, V
CC
= 5.5V, f
I
=
10Mhz, outputs open, one bit
toggling - 50% duty cycle
Outputs Open, OE = GND, T/R =
GND or V
CC
One Bit Toggling,
50% Duty Cycle
Input HIGH Current
5.5
mA
Max
I
CCD
Dynamic I
CC
(Note 3)
0.4
mA/
MHz
Max
Note 3:
Guaranteed but not tested.
3
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AC Electrical Characteristics
Symbol
Parameter
54FCT
T
A
= −55˚C to +125˚C
V
CC
= 4.5V–5.5V
C
L
= 50 pF
Min
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
Propagation Delay
Data to Outputs
Output Enable
Time
Output Disable
Time
1.5
1.5
1.5
1.5
1.5
1.5
Max
7.5
7.5
10.0
10.0
10.0
10.0
ns
ns
ns
Units
Fig.
No.
Figure
4
Figure
5
Figure
5
Capacitance
Symbol
C
IN
C
I/O
(Note 4)
Parameter
Input Capacitance
I/O Capacitance
Max
10.0
12.0
Units
pF
pF
Conditions
T
A
= 25˚C
V
CC
= 0V (OE , T/R)
V
CC
= 5.0V (A
n
, B
n
)
Note 4:
C
I/O
is measured at frequency f = 1 MHz, per MIL-STD-883B, Method 3012.
AC Loading
DS100950-6
*
Includes jig and probe capacitance
DS100950-7
FIGURE 1. Standard AC Test Load
FIGURE 2. Test Input Signal Levels
Amplitude
3.0V
Rep. Rate
1 MHz
t
w
500 ns
t
r
2.5 ns
t
f
2.5 ns
FIGURE 3. Test Input Signal Requirements
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4
AC Waveforms
DS100950-8
DS100950-10
FIGURE 4. Propagation Delay Waveforms
for Inverting and Non-Inverting Functions
FIGURE 5. TRI-STATE Output HIGH
and LOW Enable and Disable Times
5
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