54LVXC4245
8-Bit Dual Supply Configurable Voltage Interface
Transceiver with TRI-STATE
Outputs
General Description
The LVXC4245 is a 24-pin dual-supply, 8-bit configurable
voltage interface transceiver suited for real time configurable
I/O applications. The V
CCA
pin accepts a 5V supply level.
The "A" port is a dedicated 5V port. The V
CCB
pin accepts a
3V-to-5V supply level. The "B" port is configured to track the
V
CCB
supply level respectively. A 5V level on the V
CC
pin will
configure the I/O pins at a 5V level and a 3V V
CC
will config-
ure the I/O pins at a 3V level. This device will allow the V
CCB
voltage source pin and I/O pins on the "B" port to float when
OE is HIGH. This feature is necessary to buffer data to and
from a socket that permits live insertion and removal during
normal operation.
Features
n
Bidirectional interface between 5V and 3V-to-5V buses
n
Control inputs compatible with TTL level
n
Outputs source/sink up to 24 mA
n
Available in Cerpack and CDIP packages
n
Implements patented EMI reduction circuitry
n
Flexible V
CCB
operating range
n
Allows B port and V
CCB
to float simultaneously when OE
is HIGH
n
Functionally compatible with the 54 series 245
n
Standard Microcircuit Drawing (SMD) 5962-9862001
Ordering Code
Order Number
Package Number
Package Description
54LVXC4245W-QML
W24C
24-Lead Ceramic Flatpack
54LVXC4245J-QML
J24F
24-Lead Ceramic Dual-in-line
Logic Symbol
Pin Descriptions
Pin Names
Description
OE
Output Enable Input
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
Connection Diagram
TRI-STATE
is a registered trademark of National Semiconductor Corporation
DS101033-1
Pin Assignment
for Cerpack and CDIP
DS101033-2
March 1999
54L
VXC4245
8-Bit
Dual
Supply
Configurable
V
oltage
Interface
T
ransceiver
with
TRI-ST
A
T
E
Outputs
1999 National Semiconductor Corporation
DS101033
www.national.com
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
CCA
,V
CCB
)
-0.5V to +7.0V
DC Input Voltage (V
I
)
@
OE, T/R
-0.5V to V
CCA
+0.5V
DC Input/Output Voltage (V
I/O
)
@
A
n
-0.5V to V
CCA
+0.5V
@
B
n
-0.5V to V
CCB
+0.5V
DC Input Diode Current (I
IK
)
@
OE, T/R
20 mA
DC Output Diode Current (I
OK
)
50 mA
DC Output Source or
Sink Current (I
O
)
50 mA
DC V
CC
or Ground Current
Per Output Pin (I
CC
or I
GND
)
50 mA
and Max Current
200 mA
Storage Temperature Range
(T
STG
)
-65C to +150C
Recommended Operating
Conditions
(Note 2)
Supply Voltage
V
CCA
4.5V to 5.5V
V
CCB
2.7V to 5.5V
Input Voltage (V
I
)
@
OE , T/R
0V to V
CCA
Input/Output Voltage (V
I/O
)
@
A
n
0V to V
CCA
@
B
n
0V to V
CCB
Free Air Operating Temperature (T
A
)
-55C to +125C
Minimum Input Edge Rate (
V/
t)
8 ns/V
V
IN
from 30% to 70% of V
CC
V
CC
@
3V, 4.5V, 5.5V
Note 1: The "Absolute Maximum Ratings" are those values beyond which
the safety of the device cannot be guaranteed. The device should not be op-
erated at these limits. The parametric values defined in the Electrical Charac-
teristics tables are not guaranteed at the absolute maximum ratings. The
"Recommended Operating Conditions" table will define the conditions for ac-
tual device operation.
Note 2: The A port unused pins (inputs and I/O's) must be held HIGH or
LOW. They may not float.
DC Electrical Characteristics
Symbol
Parameter
V
CCA
(V)
V
CCB
(V)
T
A
= -55C to
+125C
Units
Conditions
Guaranteed Limits
V
IHA
Minimum High Level
A
n
4.5
2.7
2.0
V
V
OUT
0.1V
Input Voltage
OE
4.5
3.6
2.0
or
T/R
5.5
5.5
2.0
V
CC
- 0.1V
V
IHB
B
n
4.5
2.7
2.0
4.5
3.6
2.0
4.5
5.5
3.85
V
ILA
Maximum Low Level
A
n
4.5
2.7
0.8
V
V
OUT
0.1V
Input Voltage
OE
4.5
3.6
0.8
or
T/R
5.5
5.5
0.8
V
CC
- 0.1V
V
ILB
B
n
4.5
2.7
0.8
4.5
3.6
0.8
4.5
5.5
1.65
V
OHA
Minimum High Level
4.5
2.7
4.4
V
I
OH
= -100 A
Output Voltage
5.5
5.5
5.4
I
OH
= -100 A
4.5
3.0
3.7
I
OH
= -24 mA
4.5
4.5
3.7
I
OH
= -24 mA
V
OHB
4.5
2.7
2.6
V
I
OH
= -100 A
5.5
5.5
5.4
I
OH
= -100 A
4.5
2.7
2.2
I
OH
= -12 mA
4.5
3.0
2.4
I
OH
= -12 mA
4.5
3.0
2.2
I
OH
= -24 mA
4.5
4.5
3.7
I
OH
= -24 mA
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3
DC Electrical Characteristics
(Continued)
Symbol
Parameter
V
CCA
(V)
V
CCB
(V)
T
A
= -55C to
+125C
Units
Conditions
Guaranteed Limits
V
OLA
Maximum Low Level
4.5
2.7
0.1
V
I
OL
= 100 A
Output Voltage
5.5
5.5
0.1
I
OL
= 100 A
4.5
3.0
0.4
I
OL
= 24 mA
4.5
4.5
0.4
I
OL
= 24 mA
V
OLB
4.5
2.7
0.1
V
I
OL
= 100 A
5.5
5.5
0.1
I
OL
= 100 A
4.5
2.7
0.3
I
OL
= 12 mA
4.5
3.0
0.3
I
OL
= 12 mA
4.5
3.0
0.4
I
OL
= 24 mA
4.5
4.5
0.4
I
OL
= 24 mA
I
IN
Maximum Input Leakage
5.5
3.6
1.0
A
V
I
= V
CCA
, GND
Current
@
OE, T/R
5.5
5.5
1.0
I
OZA
Maximum TRI-STATE
5.5
3.6
5.0
A
V
I
= V
IL
, V
IH
Output Leakage
@
A
n
5.5
5.5
5.0
OE = V
CCA
V
O
= V
CCA
, GND
I
OZB
Maximum TRI-STATE
5.5
3.6
5.0
A
V
I
= V
IL
, V
IH
,
Output Leakage
@
B
n
5.5
5.5
5.0
OE = V
CCA
V
O
= V
CCB
, GND
I
CC
Maximum
All
Inputs
5.5
5.5
1.5
mA
V
I
= V
CC
- 2.1V
I
CC
/Input
B
n
5.5
3.6
0.5
mA
V
I
= V
CCB
- 0.6V
I
CCA1
Quiescent V
CCA
A
n
= V
CCA
or GND
Supply Current as B Port Floats
5.5
Open
40
A
B
n
= Open, OE =
V
CCA
T/R = V
CCA
, V
CCB
=
Open
I
CCA2
Quiescent V
CCA
A
n
= V
CCA
or GND
Supply Current
5.5
3.6
40
A
B
n
= V
CCB
or GND
5.5
5.5
40
OE = GND, T/R =
GND
I
CCB
Quiescent V
CCB
A
n
= V
CCA
or GND
Supply Current
5.5
3.6
10
A
B
n
= V
CCB
or GND
5.5
5.5
40
OE = GND, T/R =
V
CCA
V
OLPA
Quiet Output Maximum
5.0
3.3
1.5
V
(Note 3)
Dynamic V
OL
5.0
5.0
1.5
V
OLPB
5.0
3.3
0.8
V
(Note 3)
5.0
5.0
1.5
V
OLVA
Quiet Output Minimum
5.0
3.3
-1.1
V
(Note 3)
Dynamic V
OL
5.0
5.0
-1.2
V
OLVB
5.0
3.3
-0.7
V
(Note 3)
5.0
5.0
-1.1
Note 3: Max number of outputs defined as (n). Data inputs are driven 0V to V
CC
level; one output at GND.
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4
AC Electrical Characteristics
Symbol
Parameter
C
L
= 50 pF
C
L
= 50 pF
Units
V
CCA
= 4.5V to 5.5V
V
CCA
= 4.5V to 5.5V
V
CCB
= 4.5V to 5.5V
V
CCB
= 2.7V to 3.6V
T
A
= -55C to +125C
T
A
= -55C to +125C
Min
Max
Min
Max
t
PHL
Propagation
1.0
8.0
1.0
9.5
ns
t
PLH
Delay A to B
1.0
8.0
1.0
9.5
t
PHL
Propagation
1.0
8.0
1.0
9.5
ns
t
PLH
Delay B to A
1.0
8.0
1.0
9.5
t
PZL
Output Enable
1.0
9.5
1.0
12.0
ns
t
PZH
Time OE to B
1.0
9.5
1.0
12.0
t
PZL
Output Enable
1.0
11.5
1.0
13.0
ns
t
PZH
Time OE to A
1.0
11.5
1.0
13.0
t
PHZ
Output Disable
1.0
7.0
1.0
7.5
ns
t
PLZ
Time OE to B
1.0
7.0
1.0
7.5
t
PHZ
Output Disable
0.5
7.0
0.5
7.0
ns
t
PLZ
Time OE to A
0.5
7.0
0.5
7.0
t
OSHL
Output to Output
t
OSLH
Skew (Note 4)
1.5
1.5
ns
Data to Output
Note 4: Skew is defined as the absolute value of the difference between the actual propagation delay for any two separate outputs of the same device. The speci-
fication applies to any outputs switching in the same direction, either HIGH to LOW (t
OSHL
) or LOW to HIGH (t
OSLH
). Parameter guaranteed by design.
Capacitance
Symbol
Parameter
Max
Units
Conditions
C
IN
Input Capacitance
10
pF
V
CC
= Open
C
I/O
Input/Output Capacitance
12
pF
V
CCA
= 5V, V
CCB
= 3.3V
C
PD
Power Dissipation Capacitance
A
B
50
pF
V
CCA
= 5V
B
A
50
pF
V
CCB
= 3.3V
Note 5: C
PD
is measured at 10 MHz.
www.national.com
5
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