54LVX3245
8-Bit Dual Supply Translating Transceiver with
TRI-STATE
Outputs
General Description
The LVX3245 is a dual-supply, 8-bit translating transceiver
that is designed to interface between a 3V bus and a 5V bus
in a mixed 3V/5V supply environment. The Transmit/Receive
(T/R) input determines the direction of data flow. Transmit
(active-HIGH) enables data from A ports to B ports; Receive
(active-LOW) enables data from B ports to A ports. The Out-
put Enable input, when HIGH, disables both A and B ports by
placing them in a TRI-STATE condition. The A port interfaces
with the 3V bus; the B port interfaces with the 5V bus.
The LVX3245 is suitable for mixed voltage applications such
as systems using 3.3V memories which must interface with
existing busses or other components operating at 5.0V.
Features
n
Bidirectional interface between 3V and 5V buses
n
Inputs compatible with TTL level
n
3V data flow at A port and 5V data flow at B port
n
Outputs source/sink 24 mA
n
Available in ceramic DIP and Flatpack packages
n
Implements proprietary EMI reduction circuitry
n
Functionally compatible with the 54 series 245
n
Standard Microcircuit Drawing (SMD) 5962-9860501
Ordering Code
Order Number
Package Number
Package Description
54LVX3245J-QML
J24F
24-Lead Ceramic Dual-in-line
54LVX3245W-QML
W24C
24-Lead Cerpack
Logic Symbol
Connection Diagram
TRI-STATE
is a registered trademark of National Semiconductor Corporation.
DS101018-1
Pin Assignment
for CDIP and Cerpack
DS101018-2
January 1999
54L
VX3245
8-Bit
Dual
Supply
T
ranslating
T
ransceiver
with
TRI-ST
A
T
E
Outputs
1999 National Semiconductor Corporation
DS101018
www.national.com
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
Truth Table
Inputs
Outputs
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
I = Immaterial
Logic Diagram
DS101018-4
www.national.com
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.
Supply Voltage (V
CCA
, V
CCB
)
-0.5V to +7.0V
DC Input Voltage (V
I
)
@
OE, T/R
-0.5V to V
CCB
+ 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
IN
)
@
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
@
I
CCA
200 mA
@
I
CCB
200 mA
Storage Temperature Range
(T
STG
)
-65C to +150C
Recommended Operating
Conditions
(Note 2)
Supply Voltage
V
CCA
2.7V to 3.6V
V
CCB
4.5V to 5.5V
Input Voltage (V
I
)
@
OE , T/R
0V to V
CCB
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 (
t/
V)
8 ns/V
V
IN
from 30% to 70% of V
CC
V
CC
@
3.0V, 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: Unused Pins (inputs and I/Os) 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 Input
Voltage
A(n), T/R,
3.6
5.0
2.0
V
V
OUT
0.1V or
V
CC
- 0.1V
OE
2.7
5.0
2.0
V
IHB
B(n)
3.3
4.5
2.0
3.3
5.5
2.0
V
ILA
Maximum Low
Level
Input Voltage
A(n), T/R,
3.6
5.0
0.8
V
V
OUT
0.1V or
V
CC
-0.1V
OE
2.7
5.0
0.8
V
ILB
B(n)
3.3
4.5
0.8
3.3
5.5
0.8
V
OHA
Minimum High Level
2.7
4.5
2.6
V
I
OH
= -100 A
Output Voltage
3.6
5.5
3.5
I
OH
= -100 A
2.7
4.5
2.2
I
OH
= -12 mA
3.0
4.5
2.4
I
OH
= -12 mA
3.0
4.5
2.2
I
OH
= -24 mA
V
OHB
2.7
4.5
4.4
V
I
OH
= -100 A
3.6
5.5
5.4
I
OH
= -100 A
3.0
4.5
3.7
I
OH
= -24 mA
V
OLA
Maximum Low Level
2.7
4.5
0.1
V
I
OL
=100 A
Output Voltage
3.6
5.5
0.1
I
OL
=100 A
2.7
4.5
0.4
I
OL
= 12 mA
3.0
4.5
0.3
I
OL
= 12 mA
3.0
4.5
0.4
I
OL
= 24 mA
V
OLB
2.7
4.5
0.1
V
I
OL
= 100 A
3.6
5.5
0.1
I
OL
= 100 A
3.0
4.5
0.4
I
OL
= 24 mA
www.national.com
3
DC Electrical Characteristics
(Continued)
Symbol
Parameter
V
CCA
(V)
V
CCB
(V)
T
A
= -55C to +125C
Units
Conditions
Guaranteed Limits
I
IN
Maximum Input
V
I
= V
CCB
, GND
Leakage Current
3.6
5.5
1.0
A
@
OE, T/R
I
OZA
Maximum TRI-STATE
T/R = 0.0V,
Output Leakage
3.6
5.5
5.0
A
OE = V
IH
@
A(n)
V
O
= V
CCA
, GND
I
OZB
Maximum TRI-STATE
T/R = 3.6V,
Output Leakage
3.6
5.5
5.0
A
OE = V
IH
@
B(n)
V
O
= V
CCB
, GND
I
CC
Maximum
B(n)
3.6
5.5
1.5
mA
V
I
= V
CCB
- 2.1V,
T/R = 0.0V
I
CCT
/Input
@
A(n), T/R,
3.6
5.5
500
A
V
I
= V
CCA
- 0.6V
OE
T/R = 3.6V
I
CCA
Quiescent V
CCA
B(n) = V
CCB
or GND
Supply Current
3.6
5.5
10
A
OE = GND,
T/R = GND
I
CCB
Quiescent V
CCB
A(n) = V
CCA
or GND
Supply Current
3.6
5.5
40
A
OE = GND,
T/R = V
CCA
V
OLPA
Quiet Output Maximum
3.3
5.0
1.1
V
(Note 4) (Note 5)
V
OLPB
Dynamic V
OL
3.3
5.0
1.6
V
OLVA
Quiet Output Minimum
3.3
5.0
-0.8
V
(Note 4) (Note 5)
V
OLVB
Dynamic V
OL
3.3
5.0
-1.1
Note 3: Maximum test duration 2.0 ms, one output loaded at a time.
Note 4: Worst case package.
Note 5: Max number of outputs defined as (n). Data inputs are driven 0V to V
CC
level; one output at GND.
www.national.com
4
AC Electrical Characteristics
Symbol
Parameters
T
A
= -55C to +125C
T
A
= -55C to +125C
Units
C
L
= 50 pF
C
L
= 50 pF
V
CCA
= 3.3V (Note 7)
V
CCA
=2.7V
V
CCB
= 5.0V (Note 6)
V
CCB
=5.0V (Note 6)
Min
Max
Min
Max
t
PHL
Propagation
Delay
1.0
8.5
1.0
9.0
ns
t
PLH
A to B
1.0
8.5
1.0
9.0
t
PHL
Propagation
Delay
1.0
8.0
1.0
8.5
ns
t
PLH
B to A
1.0
8.0
1.0
8.5
t
PZL
Output Enable
1.0
8.5
1.0
9.0
ns
t
PZH
Time OE to B
1.0
8.5
1.0
9.0
t
PZL
Output Enable
1.0
9.5
1.0
10.5
ns
t
PZH
Time OE to A
1.0
9.5
1.0
10.5
t
PHZ
Output Disable
1.0
7.5
1.0
7.5
ns
t
PLZ
Time OE to B
1.0
7.5
1.0
7.5
t
PHZ
Output Disable
1.0
7.0
1.0
7.0
ns
t
PLZ
Time OE to A
1.0
7.0
1.0
7.0
t
OSHL
Output to Output
t
OSLH
Skew (Note 8)
1.5
1.5
ns
Data to Output
Note 6: Voltage Range 5.0V is 5.0V
0.5V.
Note 7: Voltage Range 3.3V is 3.3V
0.3V.
Note 8: 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
12
pF
V
CCA
= 3.3V
Capacitance
V
CCB
= 5.0V
C
PD
Power Dissipation
50
pF
V
CCB
= 5.0V
Capacitance
V
CCA
= 3.3V
Note 9: C
PD
is measured at 10 MHz
8-Bit Dual Supply Translating Transceiver
The LVX3245 is a dual supply device capable of bidirectional
signal translation. This level shifting ability provides an effi-
cient interface between low voltage CPU local bus with
memory and a standard bus defined by 5V I/O levels. The
device control inputs can be controlled by either the low volt-
age CPU and core logic or a bus arbitrator with 5V I/O levels.
Manufactured on a sub-micron CMOS process, the LVX3245
is suitable for mixed voltage applications such as systems
using 3.3V memories which must interface with existing bus-
ses or other components operating at 5.0V.
DS101018-3
www.national.com
5
PDF 
ZIP