Philips Semiconductors
Product specification
74F138
1-of-8 decoder/demultiplexer
2
February 14, 1991
8530343 01719
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
16
15
14
13
12
11
10
7
6
5
4
3
2
1
Q7
V
CC
Q3
Q4
Q5
Q2
Q0
Q1
A0
A1
E2
A2
E0
E1
9
8
GND
Q6
SF00174
TYPE
TYPICAL
PROPAGATION
DELAY
TYPICAL
SUPPLY CURRENT
(TOTAL)
74F138
5.8ns
13mA
ORDERING INFORMATION
ORDER CODE
DESCRIPTION
COMMERCIAL RANGE
V
CC
= 5V
10%, T
amb
= 0
C to +70
C
INDUSTRIAL RANGE
V
CC
= 5V
10%, T
amb
= 40
C to +85
C
PKG DWG #
16-pin plastic DIP
N74F138N
I74F138N
SOT38-4
16-pin plastic SO
N74F138D
I74F138D
SOT109-1
INPUT AND OUTPUT LOADING AND FAN-OUT TABLE
PINS
DESCRIPTION
74F (U.L.) HIGH/LOW
LOAD VALUE HIGH/LOW
A0 A2
Address inputs
1.0/1.0
20
A/0.6mA
E0, E1
Enable inputs (active Low)
1.0/1.0
20
A/0.6mA
E2
Enable input (active High)
1.0/1.0
20
A/0.6mA
Q0 Q7
Data outputs
50/33
1.0mA/20mA
NOTE:
One (1.0) FAST unit load is defined as: 20
A in the High state and 0.6mA in the Low state.
LOGIC SYMBOL
A1 A2
A0
Q2 Q3 Q4 Q5
13 12 11 10
1
2
3
V
CC
= Pin 16
GND = Pin 8
SF00175
Q1
14
Q0
15
Q6
9
Q7
7
4
5
6
E0
E1
E2
IEC/IEEE SYMBOL
SF00176
DMUX
1
2
4
5
6
15
14
13
12
11
10
9
7
0
0
1
2
G
0
3
3
4
5
6
7
3
2
&
Philips Semiconductors
Product specification
74F138
1-of-8 decoder/demultiplexer
February 14, 1991
4
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
PARAMETER
RATING
UNIT
V
CC
Supply voltage
0.5 to +7.0
V
V
IN
Input voltage
0.5 to +7.0
V
I
IN
Input current
30 to +5
mA
V
OUT
Voltage applied to output in High output state
0.5 to V
CC
V
I
OUT
Current applied to output in Low output state
40
mA
T
Operating free air temperature range
Commercial range
0 to +70
C
T
amb
Operating free-air temperature range
Industrial range
40 to +85
C
T
stg
Storage temperature range
65 to +150
C
RECOMMENDED OPERATING CONDITIONS
SYMBOL
PARAMETER
LIMITS
UNIT
SYMBOL
PARAMETER
MIN
NOM
MAX
UNIT
V
CC
Supply voltage
4.5
5.0
5.5
V
V
IH
High-level input voltage
2.0
V
V
IL
Low-level input voltage
0.8
V
I
IK
Input clamp current
18
mA
I
OH
High-level output current
1
mA
I
OL
Low-level output current
20
mA
T
b
Operating free-air temperature range
Commercial range
0
+70
C
T
amb
O erating free-air tem erature range
Industrial range
40
+85
C
DC ELECTRICAL CHARACTERISTICS
(Over recommended operating free-air temperature range unless otherwise noted.)
SYMBOL
PARAMETER
TEST CONDITIONS
1
LIMITS
UNIT
SYMBOL
PARAMETER
TEST CONDITIONS
1
MIN
TYP
2
MAX
UNIT
V
O
High level output voltage
V
CC
= MIN, V
IL
= MAX,
I
O
= MAX
10%V
CC
2.5
V
V
OH
High-level output voltage
CC
,
IL
,
V
IH
= MIN
I
OH
= MAX
5%V
CC
2.7
3.4
V
V
O
Low level output voltage
V
CC
= MIN, V
IL
= MAX,
I
O
= MAX
10%V
CC
0.30
0.50
V
V
OL
Low-level output voltage
CC
,
IL
,
V
IH
= MIN
I
OL
= MAX
5%V
CC
0.30
0.50
V
V
IK
Input clamp voltage
V
CC
= MIN, I
I
= I
IK
0.73
1.2
V
I
I
Input current at maximum input voltage
V
CC
= MAX, V
I
= 7.0V
100
A
I
IH
High-level input current
V
CC
= MAX, V
I
= 2.7V
20
A
I
IL
Low-level input current
V
CC
= MAX, V
I
= 0.5V
0.6
mA
I
OS
Short-circuit output current
3
V
CC
= MAX
60
150
mA
I
CC
Supply current
4
(total)
V
CC
= MAX
13
20
mA
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.
Philips Semiconductors
Product specification
74F138
1-of-8 decoder/demultiplexer
February 14, 1991
5
AC ELECTRICAL CHARACTERISTICS
LIMITS
SYMBOL
PARAMETER
TEST
CONDITION
V
CC
= +5.0V
T
amb
= +25
C
C
L
= 50pF
R
L
= 500
V
CC
= +5.0V
10%
T
amb
= 0
C to +70
C
C
L
= 50pF
R
L
= 500
V
CC
= +5.0V
10%
T
amb
= 40
C to +85
C
C
L
= 50pF
R
L
= 500
UNIT
MIN
TYP
MAX
MIN
MAX
MIN
MAX
t
PLH
t
PHL
Propagation delay
An to Qn
Waveform 1, 2
3.5
4.0
5.6
6.1
7.0
8.0
3.5
4.0
8.0
9.0
3.0
3.5
8.5
9.0
ns
t
PLH
t
PHL
Propagation delay
E0 or E1
to Qn
Waveform 2
3.5
3.0
6.4
5.3
7.0
7.0
3.5
3.0
8.0
7.5
3.0
3.0
8.0
7.5
ns
t
PLH
t
PHL
Propagation delay
E2
to Qn
Waveform 1
4.0
3.5
6.2
5.6
8.0
7.5
4.0
3.5
9.0
8.5
4.0
3.5
9.5
8.5
ns
AC WAVEFORMS
For all waveforms, V
M
= 1.5V
VM
VM
VM
VM
Qn
An, E2
tPHL
tPLH
SF00179
Waveform 1.
Propagation Delay for Inverting Outputs
VM
VM
VM
VM
Qn
An, E0, E1
tPHL
tPLH
SF00180
Waveform 2. Propagation Delay for Non-Inverting Outputs
TEST CIRCUIT AND WAVEFORMS
tw
90%
VM
10%
90%
VM
10%
90%
VM
10%
90%
VM
10%
NEGATIVE
PULSE
POSITIVE
PULSE
tw
AMP (V)
0V
0V
tTHL (tf
)
INPUT PULSE REQUIREMENTS
rep. rate
t
w
t
TLH
t
THL
1MHz
500ns
2.5ns
2.5ns
Input Pulse Definition
VCC
family
74F
D.U.T.
PULSE
GENERATOR
RL
CL
RT
VIN
VOUT
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.
tTHL (tf
)
tTLH (tr
)
tTLH (tr
)
AMP (V)
amplitude
3.0V
1.5V
V
M
SF00006
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