74LCX245
LOW VOLTAGE CMOS OCTAL BUS TRANSCEIVER(3-STATE)
WITH 5V TOLERAT INPUTS AND OUTPUTS
s
s
s
s
s
s
s
s
s
s
5V TOLERANT INPUTS AND OUTPUTS
HIGH SPEED :
t
PD
= 7.0 ns (MAX.) at V
CC
= 3V
POWER DOWN PROTECTION ON INPUTS
AND OUTPUTS
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 24mA (MIN) at V
CC
= 3V
PCI BUS LEVELS GUARANTEED AT 24 mA
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 2.0V to 3.6V (1.5V Data
Retention)
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 245
LATCH-UP PERFORMANCE EXCEEDS
500mA (JESD 17)
ESD PERFORMANCE:
HBM > 2000V (MIL STD 883 method 3015);
MM > 200V
SOP
TSSOP
ORDER CODES
PACKAGE
SOP
TSSOP
TUBE
74LCX245M
T&R
74LCX245MTR
74LCX245TTR
DESCRIPTION
The 74LCX245 is a low voltage CMOS OCTAL
BUS TRANSCEIVER (3-STATE) fabricated with
sub-micron silicon gate and double-layer metal
wiring C
2
MOS technology. It is ideal for low power
and high speed 3.3V applications; it can be
interfaced to 5V signal environment for both inputs
and outputs.
PIN CONNECTION AND IEC LOGIC SYMBOLS
It has same speed performance at 3.3V than 5V
AC/ACT family, combined with a lower power
consumption.
This IC is intended for two way asynchronous
communication between data buses; the direction
of data transmission is determined by DIR input.
The enable input G can be used to disable the
device so that the buses are effectively isolated.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
All floating bus terminals during High Z state must
be held HIGH or LOW.
September 2001
1/10
74LCX245
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No
1
2, 3, 4, 5, 6, 7, 8, 9
18, 17, 16, 15, 14, 13, 12, 11
19
10
20
SYMBOL
DIR
A1 to A8
B1 to B8
G
GND
V
CC
NAME AND FUNCTION
Directional Control
Data Inputs/Outputs
Data Inputs/Outputs
Output Enable Input
Ground (0V)
Positive Supply Voltage
TRUTH TABLE
INPUTS
G
L
L
H
X : Don’t Care
Z : High Impedance
FUNCTION
OUTPUT
DIR
L
H
X
A BUS
OUTPUT
INPUT
Z
B BUS
INPUT
OUTPUT
Z
A=B
B=A
Z
2/10
74LCX245
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
I
V
O
V
O
I
IK
I
OK
I
O
I
CC
I
GND
T
stg
T
L
Supply Voltage
DC Input Voltage
DC Output Voltage (OFF State)
DC Output Voltage (High or Low State) (note 1)
DC Input Diode Current
DC Output Diode Current (note 2)
DC Output Current
DC Supply Current per Supply Pin
DC Ground Current per Supply Pin
Storage Temperature
Lead Temperature (10 sec)
Parameter
Value
-0.5 to +7.0
-0.5 to +7.0
-0.5 to +7.0
-0.5 to V
CC
+ 0.5
- 50
- 50
±
50
±
100
±
100
-65 to +150
300
Unit
V
V
V
V
mA
mA
mA
mA
mA
°C
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
1) I
O
absolute maximum rating must be observed
2) V
O
< GND
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
I
V
O
V
O
I
OH
, I
OL
I
OH
, I
OL
T
op
dt/dv
Supply Voltage (note 1)
Input Voltage
Output Voltage (OFF State)
Output Voltage (High or Low State)
High or Low Level Output Current (V
CC
= 3.0 to 3.6V)
High or Low Level Output Current (V
CC
= 2.7V)
Operating Temperature
Input Rise and Fall Time (note 2)
Parameter
Value
2.0 to 3.6
0 to 5.5
0 to 5.5
0 to V
CC
±
24
±
12
-55 to 125
0 to 10
Unit
V
V
V
V
mA
mA
°C
ns/V
1) Truth Table guaranteed: 1.5V to 3.6V
2) V
IN
from 0.8V to 2V at V
CC
= 3.0V
3/10
74LCX245
DC SPECIFICATIONS
Test Condition
Symbol
Parameter
V
CC
(V)
-40 to 85 °C
Min.
2.0
2.7 to 3.6
0.8
2.7 to 3.6
2.7
3.0
V
OL
Low Level Output
Voltage
2.7 to 3.6
2.7
3.0
I
I
I
off
I
OZ
Input Leakage
Current
Power Off Leakage
Current
High Impedance
Output Leakage
Current
Quiescent Supply
Current
I
CC
incr. per Input
2.7 to 3.6
0
2.7 to 3.6
I
O
=-100
µA
I
O
=-12 mA
I
O
=-18 mA
I
O
=-24 mA
I
O
=100
µA
I
O
=12 mA
I
O
=16 mA
I
O
=24 mA
V
I
= 0 to 5.5V
V
I
or V
O
= 5.5V
V
I
= V
IH
or V
IL
V
O
= 0 to V
CC
V
I
= V
CC
or GND
V
I
or V
O
= 3.6 to 5.5V
V
IH
= V
CC
- 0.6V
V
CC
-0.2
2.2
2.4
2.2
0.2
0.4
0.4
0.55
±
5
10
±
5
10
±
10
500
V
CC
-0.2
2.2
2.4
2.2
0.2
0.4
0.4
0.55
±
5
10
±
5
10
±
10
500
µA
µA
µA
µA
µA
V
V
0.8
V
Max.
Value
-55 to 125 °C
Min.
2.0
Max.
V
Unit
V
IH
V
IL
V
OH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
I
CC
∆I
CC
2.7 to 3.6
2.7 to 3.6
DYNAMIC SWITCHING CHARACTERISTICS
Test Condition
Symbol
Parameter
V
CC
(V)
3.3
C
L
= 50pF
V
IL
= 0V, V
IH
= 3.3V
Value
T
A
= 25 °C
Min.
Typ.
0.8
-0.8
Max.
V
Unit
V
OLP
V
OLV
Dynamic Low Level Quiet
Output (note 1)
1) Number of outputs defined as "n". Measured with "n-1" outputs switching from HIGH to LOW or LOW to HIGH. The remaining output is
measured in the LOW state.
4/10
74LCX245
AC ELECTRICAL CHARACTERISTICS
Test Condition
Symbol
Parameter
V
CC
(V)
2.7
3.0 to 3.6
2.7
3.0 to 3.6
2.7
3.0 to 3.6
3.0 to 3.6
C
L
(pF)
50
50
50
50
R
L
(Ω)
500
500
500
500
t
s
=
t
r
(ns)
2.5
2.5
2.5
2.5
-40 to 85 °C
Min.
1.5
1.5
1.5
1.5
1.5
1.5
Max.
8.0
7.0
9.5
8.5
8.5
7.5
1.0
Value
-55 to 125 °C
Min.
1.5
1.5
1.5
1.5
1.5
1.5
Max.
9.2
8.1
10.7
9.7
9.7
8.7
1.0
ns
ns
ns
ns
Unit
t
PLH
t
PHL
t
PZL
t
PZH
t
PLZ
t
PHZ
t
OSLH
t
OSHL
Propagation Delay
Time
Output Enable Time
Output Disable Time
Output To Output
Skew Time (note1,
2)
1) Skew is defined as the absolute value of the difference between the actual propagation delay for any two outputs of the same device switch-
ing in the same direction, either HIGH or LOW (t
OSLH
= | t
PLHm
- t
PLHn
|, t
OSHL
= | t
PHLm
- t
PHLn
|)
2) Parameter guaranteed by design
CAPACITIVE CHARACTERISTICS
Test Condition
Symbol
Parameter
V
CC
(V)
3.3
3.3
3.3
V
IN
= 0 to V
CC
V
IN
= 0 to V
CC
f
IN
= 10MHz
V
IN
= 0 or V
CC
Value
T
A
= 25 °C
Min.
Typ.
6
12
45
Max.
pF
pF
pF
Unit
C
IN
C
OUT
C
PD
Input Capacitance
Output Capacitance
Power Dissipation Capacitance
(note 1)
1) C
PD
is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
CC(opr)
= C
PD
x V
CC
x f
IN
+ I
CC
/8 (per circuit)
5/10
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