INTEGRATED CIRCUITS
74F138
1-of-8 decoder/demultiplexer
Product specification
IC15 Data Handbook
1991 Feb 14
Philips
Semiconductors
Philips Semiconductors
Product specification
1-of-8 decoder/demultiplexer
74F138
FEATURE
•
Demultiplexing capability
•
Multiple input enable for easy expansion
•
Ideal for memory chip select decoding
•
Industrial temperature range available (–40°C to +85°C)
DESCRIPTION
The 74F138 decoder accepts three binary weighted inputs (A0, A1,
A2) and when enabled, provides eight mutually exclusive, active low
outputs (Q0 – Q7). The device features three enable inputs; two
active low (E0, E1) and one active high (E2). Every output will be
high unless E0 and E1 are low and E2 is high. This multiple enable
function allows easy parallel expansion of the device to 1-of-32
(5 lines to 32 lines) decoder with just four 74F138s and one inverter
(see Figure 1). The device can be used as an eight output
demultiplexer by using one of the active low enable inputs as the
data input and the remaining enable inputs as strobes. Enable
inputs not used must be permanently tied to their appropriate active
high or active low state.
PIN CONFIGURATION
A0
A1
A2
E0
E1
E2
Q7
GND
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
Q0
Q1
Q2
Q3
Q4
Q5
Q6
SF00174
TYPE
74F138
TYPICAL
PROPAGATION
DELAY
5.8ns
TYPICAL
SUPPLY CURRENT
(TOTAL)
13mA
ORDERING INFORMATION
ORDER CODE
DESCRIPTION
16-pin plastic DIP
16-pin plastic SO
COMMERCIAL RANGE
V
CC
= 5V
±10%,
T
amb
= 0°C to +70°C
N74F138N
N74F138D
INDUSTRIAL RANGE
V
CC
= 5V
±10%,
T
amb
= –40°C to +85°C
I74F138N
I74F138D
PKG DWG #
SOT38-4
SOT109-1
INPUT AND OUTPUT LOADING AND FAN-OUT TABLE
PINS
A0 – A2
E0, E1
E2
Q0 – Q7
Address inputs
Enable inputs (active Low)
Enable input (active High)
Data outputs
DESCRIPTION
74F (U.L.) HIGH/LOW
1.0/1.0
1.0/1.0
1.0/1.0
50/33
LOAD VALUE HIGH/LOW
20µA/0.6mA
20µA/0.6mA
20µA/0.6mA
1.0mA/20mA
NOTE:
One (1.0) FAST unit load is defined as: 20µA in the High state and 0.6mA in the Low state.
LOGIC SYMBOL
1
2
3
IEC/IEEE SYMBOL
DMUX
0
2
G
A0 A1 A2
3
2
0
3
0
1
2
3
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
4
5
15 14 13 12 11 10
9
7
6
4
14
13
12
11
1
15
4
5
6
E0
E1
E2
&
5
6
7
10
9
7
V
CC
= Pin 16
GND = Pin 8
SF00175
SF00176
February 14, 1991
2
853–0343 01719
Philips Semiconductors
Product specification
1-of-8 decoder/demultiplexer
74F138
LOGIC DIAGRAM
A2
A1
3
2
A0
1
E0
E1
E2
4
5
6
15
14
13
12
11
10
9
Q1
Q2
Q3
Q4
Q5
Q6
Q0
7
Q7
V
CC
= Pin 16
GND = Pin 8
SF00177
FUNCTION TABLE
INPUTS
E0
H
X
X
L
L
L
L
L
L
L
L
E1
X
H
X
L
L
L
L
L
L
L
L
E2
X
X
L
H
H
H
H
H
H
H
H
A0
X
X
X
L
H
L
H
L
H
L
H
A1
X
X
X
L
L
H
H
L
L
H
H
A2
X
X
X
L
L
L
L
H
H
H
H
Q0
H
H
H
L
H
H
H
H
H
H
H
Q1
H
H
H
H
L
H
H
H
H
H
H
Q2
H
H
H
H
H
L
H
H
H
H
H
OUTPUTS
Q3
H
H
H
H
H
H
L
H
H
H
H
Q4
H
H
H
H
H
H
H
L
H
H
H
Q5
H
H
H
H
H
H
H
H
L
H
H
Q6
H
H
H
H
H
H
H
H
H
L
H
Q7
H
H
H
H
H
H
H
H
H
H
L
NOTES:
H = High voltage level
L = Low voltage level
X = Don’t care
APPLICATION
A0
A1
A2
A3
A4
H
E2
E1
E0
A0 A1 A2
E2
E1
E0
A0 A1 A2
E2
E1
E0
A0 A1 A2
74F04
E2
E1
E0
A0 A1 A2
74F138
74F138
74F138
74F138
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Q0
Q31
SF00178
Figure 1. Expansion of 1-of-8 Decoding
February 14, 1991
3
Philips Semiconductors
Product specification
1-of-8 decoder/demultiplexer
74F138
ABSOLUTE MAXIMUM RATINGS
(Operation beyond the limit set forth in this table may impair the useful life of the device.
Unless otherwise noted these limits are over the operating free air temperature range.)
SYMBOL
V
CC
V
IN
I
IN
V
OUT
I
OUT
T
amb
T
stg
Supply voltage
Input voltage
Input current
Voltage applied to output in High output state
Current applied to output in Low output state
Commercial range
Operating free-air temperature range
free air
Storage temperature range
Industrial range
PARAMETER
RATING
–0.5 to +7.0
–0.5 to +7.0
–30 to +5
–0.5 to V
CC
40
0 to +70
–40 to +85
–65 to +150
UNIT
V
V
mA
V
mA
°C
°C
°C
RECOMMENDED OPERATING CONDITIONS
LIMITS
SYMBOL
V
CC
V
IH
V
IL
I
IK
I
OH
I
OL
T
amb
b
Supply voltage
High-level input voltage
Low-level input voltage
Input clamp current
High-level output current
Low-level output current
O erating
Operating free-air tem erature range
temperature
Commercial range
Industrial range
0
–40
PARAMETER
MIN
4.5
2.0
0.8
–18
–1
20
+70
+85
NOM
5.0
MAX
5.5
UNIT
V
V
V
mA
mA
mA
°C
°C
DC ELECTRICAL CHARACTERISTICS
(Over recommended operating free-air temperature range unless otherwise noted.)
SYMBOL
PARAMETER
TEST CONDITIONS
1
V
CC
= MIN, V
IL
= MAX,
,
,
V
IH
= MIN
V
CC
= MIN, V
IL
= MAX,
,
,
V
IH
= MIN
V
CC
= MIN, I
I
= I
IK
V
CC
= MAX, V
I
= 7.0V
V
CC
= MAX, V
I
= 2.7V
V
CC
= MAX, V
I
= 0.5V
V
CC
= MAX
V
CC
= MAX
–60
13
LIMITS
MIN
TYP
2
MAX
UNIT
V
3.4
0.30
0.30
–0.73
0.50
0.50
–1.2
100
20
–0.6
–150
20
V
V
V
V
µA
µA
mA
mA
mA
V
O
OH
High-level
High level output voltage
I
O
= MAX
OH
±
10%V
CC
±
5%V
CC
±
10%V
CC
±
5%V
CC
2.5
2.7
V
O
OL
V
IK
I
I
I
IH
I
IL
I
OS
I
CC
Low-level
Low level output voltage
Input clamp voltage
Input current at maximum input voltage
High-level input current
Low-level input current
Short-circuit output current
3
Supply current
4
(total)
I
O
= MAX
OL
NOTES:
1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable type.
2. All typical values are at V
CC
= 5V, T
amb
= 25°C.
3. Not more than one output should be shorted at a time. For testing I
OS
, the use of high-speed test apparatus and/or sample-and-hold
techniques are preferable in order to minimize internal heating and more accurately reflect operational values. Otherwise, prolonged shorting
of a high output may raise the chip temperature well above normal and thereby cause invalid readings in other parameter tests. In any
sequence of parameter tests, I
OS
tests should be performed last.
4. Measure I
CC
, outputs must be open, V
IN
on all inputs = 4.5V.
February 14, 1991
4
Philips Semiconductors
Product specification
1-of-8 decoder/demultiplexer
74F138
AC ELECTRICAL CHARACTERISTICS
LIMITS
TEST
CONDITION
V
CC
= +5.0V
T
amb
= +25°C
C
L
= 50pF
R
L
= 500Ω
MIN
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Propagation delay
An to Qn
Propagation delay
E0 or E1 to Qn
Propagation delay
E2 to Qn
Waveform 1, 2
Waveform 2
Waveform 1
3.5
4.0
3.5
3.0
4.0
3.5
TYP
5.6
6.1
6.4
5.3
6.2
5.6
MAX
7.0
8.0
7.0
7.0
8.0
7.5
V
CC
= +5.0V
±
10%
T
amb
= 0°C to +70°C
C
L
= 50pF
R
L
= 500Ω
MIN
3.5
4.0
3.5
3.0
4.0
3.5
MAX
8.0
9.0
8.0
7.5
9.0
8.5
V
CC
= +5.0V
±
10%
T
amb
= –40°C to +85°C
C
L
= 50pF
R
L
= 500Ω
MIN
3.0
3.5
3.0
3.0
4.0
3.5
MAX
8.5
9.0
8.0
7.5
9.5
8.5
ns
ns
ns
SYMBOL
PARAMETER
UNIT
AC WAVEFORMS
For all waveforms, V
M
= 1.5V
An, E2
V
M
t
PHL
V
M
t
PLH
An, E0, E1
V
M
t
PHL
V
M
t
PLH
Qn
V
M
V
M
Qn
V
M
V
M
SF00179
SF00180
Waveform 1. Propagation Delay for Inverting Outputs
Waveform 2.
Propagation Delay for Non-Inverting Outputs
TEST CIRCUIT AND WAVEFORMS
V
CC
NEGATIVE
PULSE
V
IN
PULSE
GENERATOR
R
T
D.U.T.
V
OUT
90%
V
M
10%
t
THL (
t
f
)
C
L
R
L
t
w
V
M
10%
t
TLH (
t
r
)
0V
90%
AMP (V)
t
TLH (
t
r
)
90%
POSITIVE
PULSE
V
M
10%
t
w
t
THL (
t
f
)
AMP (V)
90%
V
M
10%
0V
Test Circuit for Totem-Pole Outputs
DEFINITIONS:
R
L
= Load resistor;
see AC ELECTRICAL CHARACTERISTICS for value.
C
L
= Load capacitance includes jig and probe capacitance;
see AC ELECTRICAL CHARACTERISTICS for value.
R
T
= Termination resistance should be equal to Z
OUT
of
pulse generators.
Input Pulse Definition
INPUT PULSE REQUIREMENTS
family
amplitude V
M
74F
3.0V
1.5V
rep. rate
1MHz
t
w
500ns
t
TLH
2.5ns
t
THL
2.5ns
SF00006
February 14, 1991
5
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