4-54
FAST AND LS TTL DATA
MC54/74F138
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
VCC
TA
Supply Voltage
54, 74
4.5
5.0
5.5
V
Operating Ambient Temperature Range
54
–55
25
125
°
C
74
0
25
70
IOH
IOL
Output Current — High
54, 74
–1.0
mA
Output Current — Low
54, 74
20
mA
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE
(unless otherwise specified)
Limits
Symbol
Parameter
Min
Typ
Max
Unit
Test Conditions
VIH
VIL
VIK
VOH
Input HIGH Voltage
2.0
V
Guaranteed Input HIGH Voltage
Input LOW Voltage
0.8
V
Guaranteed Input LOW Voltage
Input Clamp Diode Voltage
–1.2
V
VCC = MIN, IIN = –18 mA
IOH = –1.0 mA
IOH = –1.0 mA
IOL = 20 mA
VCC = MAX, VIN = 2.7 V
VCC = MAX, VIN = 7.0 V
VCC = MAX, VIN = 0.5 V
VCC = MAX, VOUT = 0 V
VCC = MAX
Output HIGH Voltage
54, 74
2.5
V
VCC = 4.50 V
VCC = 4.75 V
VCC = MIN
74
2.7
V
VOL
IIH
Output LOW Voltage
0.5
V
Input HIGH Current
20
μ
A
0.1
mA
IIL
IOS
ICC
NOTES:
1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable device type.
2. Not more than one output should be shorted at a time, nor for more than 1 second.
Input LOW Current
–0.6
mA
Output Short Circuit Current (Note 2)
–60
–150
mA
Power Supply Current
20
mA
AC CHARACTERISTICS
54/74F
54F
74F
TA = +25
°
C
VCC = +5.0 V
CL = 50 pF
Min
TA = +25
°
C to +125
°
C
VCC = 5.0 V
±
10%
CL = 50 pF
Min
TA = 0
°
C to 70
°
C
VCC = 5.0 V
±
10%
CL = 50 pF
Min
Levels
of
Symbol
Parameter
Delay
Max
Max
Max
Unit
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
Propagation Delay,
3
3.0
7.5
3.0
12
3.0
8.5
ns
Address to Output
3.0
8.0
3.0
9.5
3.0
9.0
Enable to Output
2
3.5
7.0
3.5
11
3.5
8.0
ns
E1 or E2
Enable to Output
3.0
7.0
3.0
8.0
3.0
7.5
3
4.0
8.0
4.0
12.5
4.0
9.0
ns
E3
3.5
7.5
3.5
8.5
3.5
8.5
FUNCTIONAL DESCRIPTION
The decoder accepts three binary weighted inputs (AO, A1,
A2) and when enabled provides eight mutually exclusive
active LOW outputs (O0–O7). The F138 features three Enable
inputs, two active LOW (E1, E2) and one active HIGH (E3). All
outputs will be HIGH unless E1 and E2 are LOW and E3 is
HIGH. This multiple enable function allows easy parallel
expansion of the device to a 1-of-32 (5 lines to 32 lines)
decoder with just four F138s and one inverter.
The F138 can be used as an 8-output demultiplexer by
using one of the active LOW Enable inputs as the data input
and the other Enable inputs as strobes. The Enable inputs
which are not used must be permanently tied to their
appropriate active HIGH or active LOW states.