®
74LVX4245
OCTAL DUAL SUPPLY BUS TRANSCEIVER
PRELIMINARY DATA
s
s
s
s
s
s
s
s
s
HIGH SPEED: t
PD
= 6 ns (TYP.) at V
CC
= 3.3V
LOW POWER DISSIPATION:
I
CC
= 8
µA
(MAX.) at T
A
= 25
o
C
LOW NOISE: V
OLP
= 0.3V (TYP.) at V
CC
= 3.3V
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 4 mA (MIN)
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
OPERATING VOLTAGE RANGE:
V
CCA
(OPR) =4.5V to 5.5V (1.2V Data Retention)
V
CCB
(OPR) = 2.7V to 3.6V (1.2VData
Retention)
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 4245
IMPROVED LATCH-UP IMMUNITY
M
(Micro Package)
T
(TSSOP Package)
ORDER CODES :
74LVX4245M
74LVX4245T
speed operation while maintaining the CMOS low
power dissipation.
This IC is intended for two-way asynchronous
communication between data buses; the direction
of data trasmission is determined by DIR input.
The enable input G can be used to disable the
device so that the buses are effectively isolated.
The A-port interfaces with the 5V bus, the B-port
with the 3.3V bus.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
DESCRIPTION
The LVX4245 is a dual supply low voltage CMOS
OCTAL BUS TRANSCEIVER fabricated with
sub-micron silicon gate and double-layer metal
wiring C
2
MOS technology. Designed for use as
an interface between a 5V bus and a 3.3V bus in
mixed 5V/3.3V supply sistems, it achieves high
PIN CONNECTION AND IEC LOGIC SYMBOLS
March 1999
1/10
74LVX4245
DC SPECIFICATIONS FOR V
CCB
Symb ol
Parameter
T est Con ditio ns
V
CCA
V
CCB
(V)
(V)
V
IHB
V
ILB
V
OHB
High Level Input Voltage
Low Level Input Voltage
High Level Output
Voltage
Low Level Output
Voltage
Input Leakage Current
3 State Output Leakage
Current
Quiescent Supply
Current
5.0
5.0
5.0
5.0
4.5
4.5
4.5
V
OLB
4.5
4.5
4.5
I
IB
I
OZB
I
CCB
I
CCTB
5.5
5.5
5.5
5.5
3.6
2.7
3.6
2.7
3.0
3.0
2.7
3.0
3.0
2.7
3.6
3.6
3.6
3.6
I
O
=-100
µ
A
I
O
=-12 mA
I
O
=-8 mA
I
O
=100
µA
I
O
=12 mA
I
O
=8 mA
V
I
= V
CCA
or GND
V
IA
= V
IHA
or V
ILA
V
I/OB
= V
CCB
or GND
V
I A
=V
CCA
or GND
V
I B
=V
CCB
or GND
V
IB
= 3.4V, other
V
I
= V
CCB
or GND
2.9
2.48
2.26
0.0
0.1
0.31
0.31
±0.1
±
0.5
5
0.35
3.0
o
Value
T
A
= 25 C
Min .
2.0
2.0
0.8
0.8
2.9
2.40
2.20
0.1
0.40
0.40
±1.0
±
5.0
50
0.5
Typ.
Max.
-40 to 85 C
Min.
2.0
2.0
0.8
0.8
Max.
o
Unit
V
V
V
V
µA
µ
A
mA
mA
DYNAMIC SWITCHING CHARACTERISTICS
Symb ol
Parameter
T est Con ditio ns
V
CCA
V
CCB
(V)
(V)
V
OLPA
V
OLPB
V
IHDA
V
ILDA
V
IHDB
V
ILDB
Dynamic Low Voltage
Quiet Output (note 1, 2)
Dynamic Low Voltage
Quiet Output (note 1, 2)
Dynamic High Voltage
Input (note 1, 3)
Dynamic Low Voltage
Input (note 1, 3)
Dynamic High Voltage
Input (note 1, 3)
Dynamic Low Voltage
Input (note 1, 3)
5.0
5.0
5.0
5.0
5.0
5.0
3.3
-1.2
3.3
-0.8
3.3
3.3
3.3
3.3
0.8
0.8
2
o
Value
T
A
= 25 C
Min .
Typ.
1.0
-0.6
0.8
-0.5
2
1.2
Max.
1.5
-40 to 85 C
Min.
Max.
o
Unit
V
V
V
V
V
V
1) Worst case package
2) Max number of outputs defined as (n). Data inputs are driven 0V to 3.3V, (n -1) outputs switching and one output at GND
3) max number of data inputs (n) switching. (n-1) switching 0V to3.3V. Inputs under test switching: 3.3V to threshold (V
ILD
), 0V to threshold (V
IHD
). f=1MHz
4/10
74LVX4245
AC ELECTRICAL CHARACTERISTICS
(Input t
r
= t
f
=3 ns, V
CCA
= 4.5 to 5.5V, C
L
= 50 pF)
Symb ol
Parameter
Valu e
V
CCB
= 3±0.3 V
o
o
T
A
= 25 C
-40 to 85 C
T yp.
Max.
Min.
Max.
(*)
5.1
5.3
6.5
6.7
6.0
3.3
5.4
5.5
5.2
5.8
3.9
2.9
1.0
1.0
8.5
8.5
10.0
10.0
9.5
6.5
8.5
8.5
9.0
9.0
7.0
6.5
1.5
1.5
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
9.0
9.0
10.5
10.5
10.0
7.0
9.0
9.0
9.5
9.5
7.5
7.0
1.5
1.5
V
CCB
=2.7 V
o
-40 to 85 C
Min .
Max.
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
10.0
10.0
11.5
11.5
10.0
7.5
10.0
10.0
10.0
10.0
7.5
7.5
1.5
1.5
ns
ns
ns
ns
ns
ns
ns
Un it
Min.
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
t
OSLZ
t
OSHL
Propagation Delay
Time An to Bn
Output Enable Time
G to Bn
Output Disable Time
G to Bn
Propagation Delay
TimeBn to An
Output Enable Time
G to An
Output Disable Time
G to An
Output to Output
Skew Time (note 1, 2)
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1) Skew is defined as the absolute value of the difference between the actual propagation delay for any twooutputs of the same device switching in the
same direction, either HIGH or LOW
2) Parameter guaranteed by design
(*) Typical values at V
CCA
= 3.3V V
CCB
= 5.0V
(**) Typical values at V
CCA
= 3.3V V
CCB
=3.3V
CAPACITIVE CHARACTERISTICS
Symb ol
Parameter
T est Con ditio ns
V
CCB
V
CCA
(V)
(V)
C
INA
C
I/O
C
PD
Input Capacitance
Input/Output
Capacitance
Power Dissipation
Capacitance (note 1)
A to B
Power Dissipation
Capacitance (note 1)
B to A
open
3.3
3.3
open
5.0
5.0
o
Valu e
T
A
= 25 C
Min.
T yp.
4.5
10
55
Max.
-40 to 85 C
Min.
Max.
o
Un it
pF
pF
pF
C
PD
3.3
5.0
40
pF
1) C
PD
isdefined as the value of the IC’sinternal equivalent capacitance which is calculated fromthe operating current consumption without load. (Referto
Test Circuit).Average operting current can be obtained by the following equation. I
CC
(opr) = C
PD
•
V
CC
•f
IN
+ I
CC
/8(per circuit)
5/10
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