74LCX240
LOW VOLTAGE CMOS OCTAL BUS BUFFER (3-STATE INV.)
WITH 5V TOLERANT INPUTS AND OUTPUTS
s
s
s
s
s
s
s
s
s
s
5V TOLERANT INPUTS AND OUTPUTS
HIGH SPEED:
t
PD
= 6.5 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 240
LATCH-UP PERFORMANCE EXCEEDS
500mA (JESD 17)
ESD PERFORMANCE:
HBM > 2000V (MIL STD 883 method 3015);
MM > 200V
SOP
TSSOP
Table 1: Order Codes
PACKAGE
SOP
TSSOP
T&R
DESCRIPTION
The 74LCX240 is a low voltage CMOS OCTAL
BUS BUFFER fabricated with sub-micron silicon
gate and double-layer metal wiring C
2
MOS
technology. It is ideal for low power and high
Figure 1: Pin Connection And IEC Logic Symbols
so
b
O
r
P
te
le
du
o
(s
ct
-
)
so
b
O
speed 3.3V applications; it can be interfaced to 5V
signal environment for both inputs and outputs.
It has same speed performance at 3.3V than 5V
AC/ACT family, combined with a lower power
consumption.
This device is designed to be used with 3 state
memory address drivers, etc.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
te
le
ro
P
uc
d
74LCX240MTR
74LCX240TTR
s)
t(
September 2004
Rev. 6
1/12
74LCX240
Figure 2: Input And Output Equivalent Circuit
Table 2: Pin Description
PIN N°
1
2, 4, 6, 8
9, 7, 5, 3
11, 13, 15,
17
18, 16, 14,
12
19
10
20
SYMBOL
1G
1A1 to 1A4
2Y1 to 2Y4
2A1 to 2A4
1Y1 to 1Y4
2G
GND
V
CC
NAME AND FUNCTION
Output Enable Input
Data Inputs
Data Outputs
Data Inputs
Data Outputs
Output Enable Input
Ground (0V)
Positive Supply Voltage
Table 3: Truth Table
INPUT
G
L
L
H
An
Table 4: Absolute Maximum Ratings
Symbol
V
CC
V
I
V
O
V
O
I
IK
Supply Voltage
b
O
so
I
OK
I
O
I
CC
T
stg
T
L
ro
P
te
le
DC Input Voltage
DC Output Current
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 Supply Current per Supply Pin
DC Ground Current per Supply Pin
Storage Temperature
Lead Temperature (10 sec)
du
(s
ct
-
)
bs
O
X : Don’t Care
Z : High Impedance
et
l
o
P
e
od
r
L
H
X
uc
OUTPUT
Yn
H
L
Z
s)
t(
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
I
GND
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
2/12
74LCX240
Table 5: 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
Table 6: DC Specifications
Test Condition
Symbol
Parameter
V
CC
(V)
-40 to 85 °C
Min.
2.0
2.7 to 3.6
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
I
O
=-100
µA
I
O
=-12 mA
I
O
=-18 mA
I
O
=-24 mA
V
CC
-0.2
2.2
2.4
2.2
0.2
0.4
0.4
0.55
±
5
10
±
5
10
±
10
500
Max.
Value
-55 to 125 °C
Min.
V
IH
V
IL
V
OH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
b
O
∆I
CC
so
I
CC
ro
P
te
le
du
2.7 to 3.6
0
(s
ct
-
)
I
O
=100
µA
I
O
=12 mA
I
O
=16 mA
I
O
=24 mA
so
b
O
et
l
P
e
0.8
ro
2.0
uc
d
Max.
s)
t(
Unit
V
V
0.8
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
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
2.7 to 3.6
2.7 to 3.6
2.7 to 3.6
3/12
74LCX240
Table 7: 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.
Table 8: 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.
7.5
6.5
9.0
8.0
8.0
7.0
1.0
Value
-55 to 125 °C
Min.
1.5
1.5
1.5
1.5
1.5
1.5
Max.
8.5
7.5
10.5
9.2
9.2
8.3
1.0
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
Table 9: Capacitive Characteristics
Symbol
Parameter
C
IN
C
OUT
C
PD
so
b
O
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)
ro
P
te
le
Input Capacitance
Output Capacitance
du
(s
ct
-
)
V
CC
(V)
3.3
3.3
3.3
bs
O
et
l
o
P
e
od
r
uc
s)
t(
ns
ns
ns
ns
Test Condition
Value
T
A
= 25 °C
Min.
Typ.
6
10
40
Max.
pF
pF
pF
Unit
V
IN
= 0 to V
CC
V
IN
= 0 to V
CC
f
IN
= 10MHz
V
IN
= 0 or V
CC
Power Dissipation Capacitance
(note 1)
4/12
74LCX240
Figure 3: Test Circuit
TEST
t
PLH
, t
PHL
t
PZL
, t
PLZ
t
PZH
, t
PHZ
C
L
= 50 pF or equivalent (includes jig and probe capacitance)
R
L
= R1 = 500Ω or equivalent
R
T
= Z
OUT
of pulse generator (typically 50Ω)
Figure 4: Waveform - Propagation Delays
(f=1MHz; 50% duty cycle)
so
b
O
r
P
te
le
du
o
(s
ct
-
)
bs
O
et
l
o
P
e
ro
uc
d
Open
6V
GND
SWITCH
s)
t(
5/12
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