74LVX238
LOW VOLTAGE CMOS 3 TO 8 LINE DECODER
WITH 5V TOLERANT INPUTS
s
s
s
s
s
s
s
s
s
s
s
HIGH SPEED:
t
PD
= 5.5ns (TYP.) at V
CC
= 3.3V
5V TOLERANT INPUTS
INPUT VOLTAGE LEVEL:
V
IL
=0.8V, V
IH
=2V at V
CC
=3V
LOW POWER DISSIPATION:
I
CC
= 2
µA
(MAX.) at T
A
=25°C
LOW NOISE:
V
OLP
= 0.3V (TYP.) at V
CC
= 3.3V
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 4mA (MIN)
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 2V to 3.6V (1.2V Data Retention)
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 138
IMPROVED LATCH-UP IMMUNITY
POWER DOWN PROTECTION ON INPUTS
SOP
TSSOP
Table 1: Order Codes
PACKAGE
SOP
TSSOP
T&R
74LVX238MTR
74LVX238TTR
DESCRIPTION
The 74LVX238 is a low voltage CMOS 3 TO 8
LINE DECODER fabricated with sub-micron
silicon gate and double-layer metal wiring C
2
MOS
technology. It is ideal for low power, battery
operated and low noise 3.3V applications.
If the device is enabled, 3 binary select (A, B, and
C) determine which one of the outputs will go high.
If enable input G1 is held low or either G2A or G2B
Figure 1: Pin Connection And IEC Logic Symbols
is held high, the decoding function is inhibited and
all the 8 outputs go low.
Tree enable inputs are provided to ease cascade
connection and application of address decoders
for memory systems.
Power down protection is provided on all inputs
and 0 to 7V can be accepted on inputs with no
regard to the supply voltage.
This device can be used to interface 5V to 3V
system. It combines high speed performance with
the true CMOS low power consumption.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
August 2004
Rev. 2
1/12
74LVX238
Table 4: Absolute Maximum Ratings
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
T
stg
T
L
Supply Voltage
DC Input Voltage
DC Output Voltage
DC Input Diode Current
DC Output Diode Current
DC Output Current
Storage Temperature
Lead Temperature (10 sec)
Parameter
Value
-0.5 to +7.0
-0.5 to +7.0
-0.5 to V
CC
+ 0.5
- 20
±
20
±
25
±
50
-65 to +150
300
Unit
V
V
V
mA
mA
mA
mA
°C
°C
I
CC
or I
GND
DC V
CC
or Ground Current
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied.
Table 5: Recommended Operating Conditions
Symbol
V
CC
V
I
V
O
T
op
dt/dv
Supply Voltage (note 1)
Input Voltage
Output Voltage
Operating Temperature
Input Rise and Fall Time (note 2) (V
CC
= 3.3V)
Parameter
Value
2 to 3.6
0 to 5.5
0 to V
CC
-55 to 125
0 to 100
Unit
V
V
V
°C
ns/V
1) Truth Table guaranteed: 1.2V to 3.6V
2) V
IN
from 0.8V to 2.0V
Table 6: DC Specifications
Test Condition
Symbol
Parameter
V
CC
(V)
2.0
3.0
3.6
2.0
3.0
3.6
2.0
3.0
3.0
V
OL
Low Level Output
Voltage
2.0
3.0
3.0
I
I
I
CC
Input Leakage
Current
Quiescent Supply
Current
3.6
3.6
I
O
=-50
µA
I
O
=-50
µA
I
O
=-4 mA
I
O
=50
µA
I
O
=50
µA
I
O
=4 mA
V
I
= 5V or GND
V
I
= V
CC
or GND
T
A
= 25°C
Min.
1.5
2.0
2.4
0.5
0.8
0.8
1.9
2.9
2.58
0.0
0.0
0.1
0.1
0.36
±
0.1
2
2.0
3.0
1.9
2.9
2.48
0.1
0.1
0.44
±
1
20
Typ.
Max.
Value
-40 to 85°C
Min.
1.5
2.0
2.4
0.5
0.8
0.8
1.9
2.9
2.4
0.1
0.1
0.55
±
1
20
µA
µA
V
V
Max.
-55 to 125°C
Min.
1.5
2.0
2.4
0.5
0.8
0.8
Max.
V
Unit
V
IH
High Level Input
Voltage
Low Level Input
Voltage
High Level Output
Voltage
V
IL
V
V
OH
3/12
74LVX238
Table 7: Dynamic Switching Characteristics
Test Condition
Symbol
Parameter
V
CC
(V)
3.3
3.3
C
L
= 50 pF
3.3
0.8
T
A
= 25°C
Min.
Typ.
0.3
-0.5
2
V
-0.3
Max.
0.5
Value
-40 to 85°C
Min.
Max.
-55 to 125°C
Min.
Max.
Unit
V
OLP
V
OLV
V
IHD
V
ILD
Dynamic Low
Voltage Quiet
Output (note 1, 2)
Dynamic High
Voltage Input (note
1, 3)
Dynamic Low
Voltage Input (note
1, 3)
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 to 3.3V. Inputs under test switching: 3.3V to threshold (V
ILD
), 0V to threshold
(V
IHD
), f=1MHz.
Table 8: AC Electrical Characteristics
(Input t
r
= t
f
= 3ns)
Test Condition
Symbol
Parameter
V
CC
(V)
2.7
2.7
3.3
(*)
3.3
(*)
2.7
2.7
3.3
(*)
3.3
(*)
2.7
2.7
3.3
(*)
3.3
(*)
2.7
3.3
(*)
C
L
(pF)
15
50
15
50
15
50
15
50
15
50
15
50
50
50
T
A
= 25°C
Min.
Typ.
7.1
9.6
5.5
8.0
8.7
11.2
6.8
9.3
8.8
11.3
6.9
9.4
0.5
0.5
Max.
13.8
17.3
8.8
12.3
16.3
19.8
10.6
14.1
16.0
19.5
10.4
13.9
1.0
1.0
Value
-40 to 85°C
Min.
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
Max.
16.5
20.0
10.5
14.0
19.5
23.0
12.5
16.0
18.5
22.0
11.5
15.0
1.5
1.5
-55 to 125°C
Min.
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
Max.
18.5
22.0
11.5
15.0
205
25.0
13.5
17.0
19.5
23.0
13.5
17.0
1.5
1.5
ns
ns
ns
ns
Unit
t
PLH
t
PHL
Propagation Delay
Time
A, B, C to Y
t
PLH
t
PHL
Propagation Delay
Time
G1 to Y
t
PLH
t
PHL
Propagation Delay
Time
G2A or G2B to Y
t
OSLH
t
OSHL
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
2) Parameter guaranteed by design
(*) Voltage range is 3.3V
±
0.3V
4/12
74LVX238
Table 9: Capacitive Characteristics
Test Condition
Symbol
Parameter
V
CC
(V)
3.3
3.3
f
IN
= 10MHz
T
A
= 25°C
Min.
Typ.
4
34
Max.
10
Value
-40 to 85°C
Min.
Max.
10
-55 to 125°C
Min.
Max.
10
pF
pF
Unit
C
IN
C
PD
Input 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
Figure 4: Test Circuit
C
L
=15/50pF or equivalent (includes jig and probe capacitance)
R
T
= Z
OUT
of pulse generator (typically 50Ω)
Figure 5: Waveform - Propagation Delays For Inverting Outputs
(f=1MHz; 50% duty cycle)
5/12
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