M54HC138
M74HC138
October 1992
3 TO 8 LINE DECODER (INVERTING)
B1R
(Plastic Package)
F1R
(Ceramic Package)
M1R
(Micro Package)
C1R
(Chip Carrier)
PIN CONNECTIONS (top view)
NC =
No Internal
Connection
INPUT AND OUTPUT EQUIVALENT CIRCUIT
ORDER CODES :
M54HC138F1R
M74HC138M1R
M74HC138B1R
M74HC138C1R
DESCRIPTION
.
HIGH SPEED
t
PD
= 16 ns (TYP.) AT V
CC
= 5 V
.
LOW POWER DISSIPATION
I
CC
= 4
A AT T
A
= 25
C
.
OUTPUT DRIVE CAPABILITY
10 LSTTL LOADS
.
BALANCED PROPAGATION DELAYS
t
PLH
= t
PHL
.
SYMMETRICAL OUTPUT IMPEDANCE
|I
OH
| = I
OL
.
HIGH NOISE IMMUNITY
V
NIH
= V
NIL
= 28 % V
CC
(MIN.)
.
WIDE OPERATING VOLTAGE RANGE
V
CC
(OPR) = 2 V TO 6 V
.
PIN AND FUNCTION COMPATIBLE
WITH 54/74LS138
The M54/74HC138 is a high speed CMOS 3 TO 8
LINE DECODER fabricated in silicon gate C
2
MOS
technology.
It has the same high speed performance of LSTTL
combined with true CMOS low power consumption.
If the device is enabled, 3 binary select inputs (A, B
and C) determine which one of the outputs will go
low. If enable input G1 is held low or either G2A or
G2B is held high, the decoding function is inhibited
and all the 8 outputs go high.
Three enable inputs are provided to ease cascade
connection and application of address decoders for
memory systems. All inputs are equipped with pro-
tection circuits against static discharge and tran-
sient excess voltage.
1/10
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
2 to 6
V
V
I
Input Voltage
0 to V
CC
V
V
O
Output Voltage
0 to V
CC
V
T
op
Operating Temperature: M54HC Series
M74HC Series
-55 to +125
-40 to +85
o
C
o
C
t
r
, t
f
Input Rise and Fall Time
V
CC
= 2 V
0 to 1000
ns
V
CC
= 4.5 V
0 to 500
V
CC
= 6 V
0 to 400
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
-0.5 to +7
V
V
I
DC Input Voltage
-0.5 to V
CC
+ 0.5
V
V
O
DC Output Voltage
-0.5 to V
CC
+ 0.5
V
I
IK
DC Input Diode Current
20
mA
I
OK
DC Output Diode Current
20
mA
I
O
DC Output Source Sink Current Per Output Pin
25
mA
I
CC
or I
GND
DC V
CC
or Ground Current
50
mA
P
D
Power Dissipation
500 (*)
mW
T
stg
Storage Temperature
-65 to +150
o
C
T
L
Lead Temperature (10 sec)
300
o
C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied.
(*) 500 mW:
65
o
C derate to 300 mW by 10mW/
o
C: 65
o
C to 85
o
C
M54/M74HC138
3/10
AC ELECTRICAL CHARACTERISTICS (C
L
= 50 pF, Input t
r
= t
f
= 6 ns)
Symbol
Parameter
Test Conditions
Value
Unit
V
CC
(V)
T
A
= 25
o
C
54HC and 74HC
-40 to 85
o
C
74HC
-55 to 125
o
C
54HC
Min.
Typ.
Max.
Min.
Max.
Min.
Max.
t
TLH
t
THL
Output Transition
Time
2.0
30
75
95
110
ns
4.5
8
15
19
22
6.0
7
13
16
19
t
PLH
t
PHL
Propagation
Delay Time
(A, B, C - Y)
2.0
60
125
155
190
ns
4.5
15
25
31
38
6.0
13
21
26
32
t
PLH
t
PHL
Propagation
Delay Time
(G, G - Y)
2.0
56
120
150
180
ns
4.5
14
24
30
36
6.0
12
20
26
31
C
IN
Input Capacitance
5
10
10
10
pF
C
PD
(*)
Power Dissipation
Capacitance
47
pF
(*) 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 operting current can be obtained by the following equation. I
CC
(opr) = C
PD
V
CC
f
IN
+ I
CC
TEST CIRCUIT I
CC
(Opr.)
SWITCHING CHARACTERISTICS TEST WAVEFORM
INPUT WAVEFORM IS THE SAME
AS THAT IN CASE OF SWITCHING
CHARACTERISTICS TEST.
M54/M74HC138
5/10
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