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
Package
Package Description
Number
54FCT245DMQB
J20A
20-Lead Ceramic Dual-In-Line
54FCT245FMQB
W20A
20-Lead Cerpak
54FCT245LMQB
E20A
20-Lead Ceramic Leadless Chip Carrier, Type C
Logic Symbol
TRI-STATE
is a registered trademark of National Semiconductor Corporation.
DS100950-1
August 1998
54FCT245
Octal
Bidirectional
T
ransceiver
with
TRI-ST
A
T
E
Outputs
1998 National Semiconductor Corporation
DS100950
www.national.com
Connection Diagrams
Pin Descriptions
Pin Names
Description
OE
Output Enable Input (Active LOW)
T/R
Transmit/Receive Input
A
0
A
7
Side A Inputs or TRI-STATE Outputs
B
0
B
7
Side B Inputs or TRI-STATE Outputs
Truth Table
Inputs
Output
OE
T/R
L
L
Bus B Data to Bus A
L
H
Bus A Data to Bus B
H
X
High Z State
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Logic Diagram
Pin Assignment for DIP
and Flatpak.
DS100950-5
Pin Assignment for LCC
DS100950-3
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
-65C to +150C
Ambient Temperature under Bias
-55C to +125C
Junction Temperature under Bias
Ceramic
-55C to +175C
V
CC
Pin Potential to
Ground Pin
-0.5V to +7.0V
Input Voltage (Note 2)
-0.5V to +7.0V
Input Current (Note 2)
-30 mA to +5.0 mA
Voltage Applied to Any Output
in the Disabled or
Power-off State
-0.5V to 5.5V
in the HIGH State
-0.5V to V
CC
Current Applied to Output
in LOW State (Max)
twice the rated I
OL
(mA)
Recommended Operating
Conditions
Free Air Ambient Temperature
Military
-55C to +125C
Supply Voltage
Military
+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.
DC Electrical Characteristics
Symbol
Parameter
FCT245
Units
V
CC
Conditions
Min
Max
V
IH
Input HIGH Voltage
2.0
V
Recognized HIGH Signal
V
IL
Input LOW Voltage
0.8
V
Recognized LOW Signal
V
CD
Input Clamp Diode Voltage
-1.2
V
Min
I
IN
= -18 mA (OE, T/R)
V
OH
Output HIGH
Voltage
54FCT
4.3
V
Min
I
OH
= -300 uA (A
n
, B
n
)
54FCT
2.4
V
Min
I
OH
= -12 mA (A
n
, B
n
)
V
OL
Output LOW
Voltage
54FCT
0.2
V
Min
I
OL
= 300 uA (A
n
, B
n
)
54FCT
0.55
V
Min
I
OL
= 48 mA (A
n
, B
n
)
I
IH
Input HIGH Current
5
A
Max
V
IN
= 2.7V (OE, T/R)
5
V
IN
= V
CC
(OE, T/R)
I
BVIT
Input HIGH Current Breakdown Test
(I/O)
20
A
Max
V
IN
= 5.5V (A
n
, B
n
)
I
IL
Input LOW Current
-5
A
Max
V
IN
= 0.0V (OE, T/R)
I
OS
Output Short-Circuit Current
-60
mA
Max
V
OUT
= 0.0V (A
n
, B
n
)
I
CCQ
Power Supply Current
1.5
mA
Max
V
IN
= 0.2V or V
IN
= 5.3V, V
CC
=
5.5V
I
CC
Power Supply Current
2.0
mA
Max
V
CC
= 5.5V, V
IN
= 3.4V
I
CCT
Total Power Supply Current
6.0
mA
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
5.5
mA
Max
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
I
CCD
Dynamic I
CC
(Note 3)
0.4
mA/
MHz
Max
Outputs Open, OE =GND, T/R =
GND or V
CC
One Bit Toggling,
50% Duty Cycle
Note 3: Guaranteed but not tested.
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3
AC Electrical Characteristics
Symbol
Parameter
54FCT
Units
Fig.
No.
T
A
= -55C to +125C
V
CC
= 4.5V5.5V
C
L
= 50 pF
Min
Max
t
PLH
Propagation Delay
1.5
7.5
ns
Figure
4
t
PHL
Data to Outputs
1.5
7.5
t
PZH
Output Enable
1.5
10.0
ns
Figure
5
t
PZL
Time
1.5
10.0
t
PHZ
Output Disable
1.5
10.0
ns
Figure
5
t
PLZ
Time
1.5
10.0
Capacitance
Symbol
Parameter
Max
Units
Conditions
T
A
= 25C
C
IN
Input Capacitance
10.0
pF
V
CC
= 0V (OE , T/R)
C
I/O
(Note 4)
I/O Capacitance
12.0
pF
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
FIGURE 1. Standard AC Test Load
DS100950-7
FIGURE 2. Test Input Signal Levels
Amplitude
Rep. Rate
t
w
t
r
t
f
3.0V
1 MHz
500 ns
2.5 ns
2.5 ns
FIGURE 3. Test Input Signal Requirements
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4
AC Waveforms
DS100950-8
FIGURE 4. Propagation Delay Waveforms
for Inverting and Non-Inverting Functions
DS100950-10
FIGURE 5. TRI-STATE Output HIGH
and LOW Enable and Disable Times
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5
6
Physical Dimensions
inches (millimeters) unless otherwise noted
20-Terminal Ceramic Chip Carrier (L)
NS Package Number E20A
20-Lead Ceramic Dual-In-Line Package (D)
NS Package Number J20A
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7
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
LIFE SUPPORT POLICY
NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DE-
VICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMI-
CONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or sys-
tems which, (a) are intended for surgical implant into
the body, or (b) support or sustain life, and whose fail-
ure to perform when properly used in accordance
with instructions for use provided in the labeling, can
be reasonably expected to result in a significant injury
to the user.
2. A critical component in any component of a life support
device or system whose failure to perform can be rea-
sonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
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www.national.com
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Japan Ltd.
Tel: 81-3-5620-6175
Fax: 81-3-5620-6179
20-Lead Ceramic Flatpak (F)
NS Package Number W20A
54FCT245
Octal
Bidirectional
T
ransceiver
with
TRI-ST
A
T
E
Outputs
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
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