M54HC148
M74HC148
October 1992
8 TO 3 LINE PRIORITY ENCODER
B1R
(Plastic Package)
ORDER CODES :
M54HC148F1R
M74HC148M1R
M74HC148B1R
M74HC148C1R
F1R
(Ceramic Package)
M1R
(Micro Package)
C1R
(Chip Carrier)
PIN CONNECTIONS (top view)
NC =
No Internal
Connection
INPUT AND OUTPUT EQUIVALENT CIRCUIT
DESCRIPTION
.
HIGH SPEED
t
PD
= 15 ns (TYP.) AT V
CC
= 5 V
.
LOW POWER DISSIPATION
I
CC
= 4
A (MAX.) AT T
A
= 25
C
.
HIGH NOISE IMMUNITY
V
NIH
= V
NIL
= 28 % V
CC
(MIN.)
.
OUTPUT DRIVE CAPABILITY
10 LSTTL LOADS
.
SYMMETRICAL OUTPUT IMPEDANCE
I
OH
= I
OL
= 4 mA (MIN.)
.
BALANCED PROPAGATION DELAYS
t
PLH
= t
PHL
.
WIDE OPERATING VOLTAGE RANGE
V
CC
(OPR) = 2 V TO 6 V
.
PIN AND FUNCTION COMPATIBLE
WITH 54/74LS148
The M54/74HC148 is a high speed CMOS 8-TO-3
LINE PRIORITY ENCODER fabricated in silicon
gate C
2
MOS technology.
It has the same high speed performance for LSTTL
combined with true CMOS low power consumption.
The M54/74HC148 encodes eight data lines to
three-line (4-2-1) binary (octal). Cascading circuitry
(enable input EI and enable output EO) has been
provided to allow octal expansion without the need
for external circuitry. Data inputs are active at the
low logic level.
All inputs are equipped with protection circuits
against static discharge and transient excess volt-
age.
1/11
TRUTH TABLE
INPUTS
OUTPUTS
E1
0
1
2
3
4
5
6
7
A2
A1
A0
GS
E0
H
X
X
X
X
X
X
X
X
H
H
H
H
H
L
H
H
H
H
H
H
H
H
H
H
H
H
L
L
X
X
X
X
X
X
X
L
L
L
L
L
H
L
X
X
X
X
X
X
L
H
L
L
H
L
H
L
X
X
X
X
X
L
H
H
L
H
L
L
H
L
X
X
X
X
L
H
H
H
L
H
H
L
H
L
X
X
X
L
H
H
H
H
H
L
L
L
H
L
X
X
L
H
H
H
H
H
H
LL
H
L
H
L
X
L
H
H
H
H
H
H
H
H
L
L
H
L
L
H
H
H
H
H
H
H
H
H
H
L
H
X: Don't Care
LOGIC DIAGRAM
M54/M74HC148
2/11
PIN DESCRIPTION
PIN No
SYMBOL
NAME AND FUNCTION
9, 7, 6
A0 to A2
Data Outputs
11, 12, 13,
1, 2, 3, 4,
10
0 to 7
Data Inputs
15
EO
Enable Output
5
EI
Enable Input
14
GS
Priority Flag Output
8
GND
Ground (0V)
16
V
CC
Positive Supply Voltage
IEC LOGIC SYMBOL
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
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
M54/M74HC148
3/11
DC SPECIFICATIONS
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.
V
IH
High Level Input
Voltage
2.0
1.5
1.5
1.5
V
4.5
3.15
3.15
3.15
6.0
4.2
4.2
4.2
V
IL
Low Level Input
Voltage
2.0
0.5
0.5
0.5
V
4.5
1.35
1.35
1.35
6.0
1.8
1.8
1.8
V
OH
High Level
Output Voltage
2.0
V
I
=
V
IH
or
V
IL
I
O
=-20
A
1.9
2.0
1.9
1.9
V
4.5
4.4
4.5
4.4
4.4
6.0
5.9
6.0
5.9
5.9
4.5
I
O
=-4.0 mA
4.18
4.31
4.13
4.10
6.0
I
O
=-5.2 mA
5.68
5.8
5.63
5.60
V
OL
Low Level Output
Voltage
2.0
V
I
=
V
IH
or
V
IL
I
O
= 20
A
0.0
0.1
0.1
0.1
V
4.5
0.0
0.1
0.1
0.1
6.0
0.0
0.1
0.1
0.1
4.5
I
O
= 4.0 mA
0.17
0.26
0.33
0.40
6.0
I
O
= 5.2 mA
0.18
0.26
0.33
0.40
I
I
Input Leakage
Current
6.0
V
I
= V
CC
or GND
0.1
1
1
A
I
CC
Quiescent Supply
Current
6.0
V
I
= V
CC
or GND
4
40
80
A
M54/M74HC148
4/11
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
(In - A0, A1, A2)
2.0
60
150
190
225
ns
4.5
19
30
38
45
6.0
16
26
32
38
t
PLH
t
PHL
Propagation
Delay Time
(In - EO, GS)
2.0
60
150
190
225
ns
4.5
19
30
38
45
6.0
16
26
32
38
t
PLH
t
PHL
Propagation
Delay Time
(EI - EO)
2.0
40
115
145
175
ns
4.5
14
23
29
35
6.0
12
20
25
30
t
PLH
t
PHL
Propagation
Delay Time
(EI - GS)
2.0
40
115
145
175
ns
4.5
14
23
29
35
6.0
12
20
25
30
t
PLH
t
PHL
Propagation
Delay Time
(EI - A0, A1, A2)
2.0
40
115
145
175
ns
4.5
14
23
29
35
6.0
12
20
25
30
C
IN
Input Capacitance
5
10
10
10
pF
C
PD
(*)
Power Dissipation
Capacitance
60
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
INPUT WAVEFORM IS THE SAME AS THAT IN CASE OF
SWITCHING CHARACTERISTICS TEST.
SWITCHING CHARACTERISTICS TEST
CIRCUIT
TEST CIRCUIT I
CC
(Opr.)
M54/M74HC148
5/11
TYPICAL APPLICATION
4-BIT CASCADE CONNECTION
M54/M74HC148
6/11
Plastic DIP16 (0.25) MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
a1
0.51
0.020
B
0.77
1.65
0.030
0.065
b
0.5
0.020
b1
0.25
0.010
D
20
0.787
E
8.5
0.335
e
2.54
0.100
e3
17.78
0.700
F
7.1
0.280
I
5.1
0.201
L
3.3
0.130
Z
1.27
0.050
P001C
M54/M74HC148
7/11
Ceramic DIP16/1 MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
20
0.787
B
7
0.276
D
3.3
0.130
E
0.38
0.015
e3
17.78
0.700
F
2.29
2.79
0.090
0.110
G
0.4
0.55
0.016
0.022
H
1.17
1.52
0.046
0.060
L
0.22
0.31
0.009
0.012
M
0.51
1.27
0.020
0.050
N
10.3
0.406
P
7.8
8.05
0.307
0.317
Q
5.08
0.200
P053D
M54/M74HC148
8/11
SO16 (Narrow) MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
1.75
0.068
a1
0.1
0.2
0.004
0.007
a2
1.65
0.064
b
0.35
0.46
0.013
0.018
b1
0.19
0.25
0.007
0.010
C
0.5
0.019
c1
45
(typ.)
D
9.8
10
0.385
0.393
E
5.8
6.2
0.228
0.244
e
1.27
0.050
e3
8.89
0.350
F
3.8
4.0
0.149
0.157
G
4.6
5.3
0.181
0.208
L
0.5
1.27
0.019
0.050
M
0.62
0.024
S
8
(max.)
P013H
M54/M74HC148
9/11
PLCC20 MECHANICAL DATA
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
9.78
10.03
0.385
0.395
B
8.89
9.04
0.350
0.356
D
4.2
4.57
0.165
0.180
d1
2.54
0.100
d2
0.56
0.022
E
7.37
8.38
0.290
0.330
e
1.27
0.050
e3
5.08
0.200
F
0.38
0.015
G
0.101
0.004
M
1.27
0.050
M1
1.14
0.045
P027A
M54/M74HC148
10/11
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may results from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express
written approval of SGS-THOMSON Microelectonics.
1994 SGS-THOMSON Microelectronics - All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands -
Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A
M54/M74HC148
11/11
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