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10-LINE-TO-4-LINE AND 8-LINE-TO-3-LINE PRIORITY ENCODERS
The SN54 / 74LS147 and the SN54/ 74LS148 are Priority Encoders. They provide priority decoding of the inputs to ensure that only the highest order data line is encoded. Both devices have data inputs and outputs which are active at the low logic level. The LS147 encodes nine data lines to four-line (8-4-2-1) BCD. The implied decimal zero condition does not require an input condition because zero is encoded when all nine data lines are at a high logic level. The LS148 encodes eight data lines to three-line (4-2-1) binary (octal). By providing cascading circuitry (Enable Input EI and Enable Output EO) octal expansion is allowed without needing external circuitry. The SN54 / 74LS748 is a proprietary Motorola part incorporating a built-in deglitcher network which minimizes glitches on the GS output. The glitch occurs on the negative going transition of the EI input when data inputs 0 - 7 are at logical ones. The only dc parameter differences between the LS148 and the LS748 are that (1) Pin 10 (input 0) has a fan-in of 2 on the LS748 versus a fan-in of 1 on the LS148; (2) Pins 1, 2, 3, 4, 11, 12 and 13 (inputs 1, 2, 3, 4, 5, 6, 7) have a fan-in of 3 on the LS748 versus a fan-in of 2 on the LS148. The only ac difference is that tPHL from EI to EO is changed from 40 to 45 ns. SN54 / 74LS147 (TOP VIEW)
OUTPUT VCC 16 NC 15 D 14 D 4 5 1 4 2 5 6 3 6 7 4 7 8 5 8 C 6 C B 7 B 8 GND 3 13 3 INPUTS 2 12 2 1 11 1 9 10 9 A OUTPUT A 9
SN54/74LS147 SN54/74LS148 SN54/74LS748
10-LINE-TO-4-LINE AND 8-LINE-TO-3-LINE PRIORITY ENCODERS
LOW POWER SCHOTTKY
J SUFFIX CERAMIC CASE 620-09
16 1
16 1
N SUFFIX PLASTIC CASE 648-08
16 1
D SUFFIX SOIC CASE 751B-03
ORDERING INFORMATION
SN54LSXXXJ SN74LSXXXN SN74LSXXXD Ceramic Plastic SOIC
INPUTS
OUTPUTS
SN54 / 74LS148 SN54 / 74LS748 (TOP VIEW)
OUTPUTS VCC 16 EO 15 EO 4 5 1 4 2 5 6 3 6 INPUTS 7 4 7 EI 5 E1 A2 6 A2 GS 14 GS 3 13 3 INPUTS 2 12 2 1 11 1 0 10 0 A0 A1 7 A1 8 GND OUTPUT A0 9
OUTPUTS
FAST AND LS TTL DATA 5-245
SN54/74LS147 * SN54/74LS148 * SN54/74LS748
SN54 / 74LS148 SN54 / 74LS748 FUNCTION TABLE
OUTPUTS 6 H X X X L H H H H H 7 H X X L H H H H H H 8 H X L H H H H H H H 9 H L H H H H H H H H D H L L H H H H H H H C H H H L L L L H H H B H H H L L H H L L H A H L H L H L H L H L EI H L L L L L L L L L 0 X H X X X X X X X L 1 X H X X X X X X L H INPUTS 2 X H X X X X X L H H 3 X H X X X X L H H H 4 X H X X X L H H H H 5 X H X X L H H H H H 6 X H X L H H H H H H 7 X H L H H H H H H H A2 H H L L L L H H H H OUTPUTS A1 H H L L H H L L H H A0 H H L H L H L H L H GS H H L L L L L L L L EO H L H H H H H H H H
SN54 / 74LS147 FUNCTION TABLE
INPUTS 1 H X X X X X X X X L 2 H X X X X X X X L H 3 H X X X X X X L H H 4 H X X X X X L H H H 5 H X X X X L H H H H
H = HIGH Logic Level, L = LOW Logic Level, X = Irrelevant
FUNCTIONAL BLOCK DIAGRAMS
1
(11) 0
(10) (15) EO
(12) 2 (9) A 1
(11)
(14) GS
(13) 3 2
(12) (8) A0
(1) 4 (7) 5 (2) 3
(13)
B 4
(1)
(3) 6 5
(2)
(7) A1
7
(4)
(6) C
(3) 6
8
(5) 7
(4)
(6) A2
9
(10)
(14)
D
(5) EI
SN54 / 74LS147
SN54 / 74LS148
FAST AND LS TTL DATA 5-246
SN54/74LS147 * SN54/74LS148 * SN54/74LS748
FUNCTIONAL BLOCK DIAGRAMS (continued)
G31
(10) 0
G13
(15) EO
(11) 1 G2 (12) 2 G3 (13) 3 G4 4 (1) G5 (2) 5 G6 (3) G7 (4) 7 G8 (5) EI G1 G28 G12 G11 G23 G10 G18 G9 G29
(14) GS
(9) A0
(7)
A1
6
(6) A2
SN54 / 74LS748
FAST AND LS TTL DATA 5-247
SN54/74LS147 * SN54/74LS148 * SN54/74LS748
GUARANTEED OPERATING RANGES
Symbol VCC TA IOH IOL Supply Voltage Operating Ambient Temperature Range Output Current -- High Output Current -- Low Parameter 54 74 54 74 54, 74 54 74 Min 4.5 4.75 - 55 0 Typ 5.0 5.0 25 25 Max 5.5 5.25 125 70 - 0.4 4.0 8.0 Unit V C mA mA
DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)
Limits Symbol VIH VIL VIK VOH Parameter Input HIGH Voltage 54 Input LOW Voltage 74 Input Clamp Diode Voltage 54 Output HIGH Voltage 74 54, 74 VOL Output LOW Voltage 74 Input HIGH Current All Others Input 0 (LS748) Inputs 1 - 7 (LS148) Inputs 1 - 7 (LS748) All Others Input 0 (LS748) Inputs 1 - 7 (LS148) Inputs 1 - 7 (LS748) Input LOW Current All Others Input 0 (LS748) Inputs 1 - 7 (LS148) Inputs 1 - 7 (LS748) Short Circuit Current (Note 1) Power Supply Current Output HIGH Output LOW - 20 0.35 0.5 20 40 40 60 0.1 0.2 0.2 0.3 - 0.4 - 0.8 - 0.8 - 1.2 - 100 17 20 V 2.7 3.5 0.25 0.4 V V 2.5 - 0.65 3.5 0.8 - 1.5 V V Min 2.0 0.7 V Typ Max Unit V Test Conditions Guaranteed Input HIGH Voltage for All Inputs Guaranteed Input LOW Voltage for All Inputs VCC = MIN, IIN = - 18 mA VCC = MIN, IOH = MAX, VIN = VIH or VIL per Truth Table IOL = 4.0 mA IOL = 8.0 mA VCC = VCC MIN, VIN = VIL or VIH per Truth Table
A
VCC = MAX, VIN = 2.7 V
IIH
mA
VCC = MAX, VIN = 7.0 V
IIL
mA
VCC = MAX, VIN = 0.4 V
IOS ICCH ICCL
mA mA mA
VCC = MAX VCC = MAX, All Inputs = 4.5 V VCC = MAX, Inputs 7 & E1 = GND All Other Inputs = 4.5 V
Note 1: Not more than one output should be shorted at a time, nor for more than 1 second.
FAST AND LS TTL DATA 5-248
SN54/74LS147 * SN54/74LS148 * SN54/74LS748
AC CHARACTERISTICS (VCC = 5.0 V, TA = 25C) SN54 / 74LS147
Symbol tPLH tPHL tPLH tPHL Any Any From (Input) Any To (Output) Any Limits Waveform In-phase output Out-of-phase output Min Typ 12 12 21 15 Max 18 ns 18 33 ns 23 CL = 15 pF, RL = 2.0 k Unit Test Conditions
SN54 / 74LS148 SN54 / 74LS748
Symbol tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL tPLH tPHL EI EO EI GS EI A0, A1, or A2 0 thru 7 GS 0 thru 7 EO 1 thru 7 A0, A1, or A2 From (Input) 1 thru 7 To (Output) A0, A1, or A2 Limits Waveform In-phase output Out-of-phase output Out-of-phase output In-phase output In-phase output In-phase output In-phase output Min Typ 14 15 20 16 7.0 25 35 9.0 16 12 12 14 12 28 30 Max 18 ns 25 36 ns 29 18 ns 40 55 ns 21 25 ns 25 17 ns 36 21 40 45 ns (LS148) (LS748) CL = 15 pF, RL = 2.0 k Unit Test Conditions
FAST AND LS TTL DATA 5-249
-A-
Case 751B-03 D Suffix 16-Pin Plastic SO-16
NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. 3. CONTROLLING DIMENSION: MILLIMETER. DIMENSION A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. 751B 01 IS OBSOLETE, NEW STANDARD 751B 03.
16
9
-B1 8
P
8 PL
0.25 (0.010)
M
B
M
R X 45 G -TD 16 PL
0.25 (0.010)
M
C
SEATING PLANE
K
T B
S
M
F
J
A
S
DIM A B C D F G J K M P R
MILLIMETERS MIN MAX
9.80 3.80 1.35 0.35 0.40 10.00 4.00 1.75 0.49 1.25
INCHES MIN MAX
0.386 0.150 0.054 0.014 0.016 0.393 0.157 0.068 0.019 0.049
1.27 BSC 0.19 0.10 0 5.80 0.25 0.25 0.25 7 6.20 0.50
0.050 BSC 0.008 0.004 0 0.229 0.010 0.009 0.009 7 0.244 0.019
Case 648-08 N Suffix 16-Pin Plastic -A16 9
NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. 3. CONTROLLING DIMENSION: INCH. DIMENSION L" TO CENTER OF LEADS WHEN FORMED PARALLEL. 4. DIMENSION B" DOES NOT INCLUDE MOLD FLASH. 5. 6. ROUNDED CORNERS OPTIONAL. 648 01 THRU 07 OBSOLETE, NEW STANDARD 648 08.
B
1 8
F S
C -TK
SEATING PLANE
L
H G D 16 PL
0.25 (0.010)
M
J
M
T
A
M
DIM A B C D F G H J K L M S
MILLIMETERS MIN MAX
18.80 6.35 3.69 0.39 1.02 19.55 6.85 4.44 0.53 1.77
INCHES MIN MAX
0.740 0.250 0.145 0.015 0.040 0.770 0.270 0.175 0.021 0.070
2.54 BSC 1.27 BSC 0.21 2.80 7.50 0 0.51 0.38 3.30 7.74 10 1.01
0.100 BSC 0.050 BSC 0.008 0.110 0.295 0 0.020 0.015 0.130 0.305 10 0.040
-A16 9
Case 620-09 J Suffix 16-Pin Ceramic Dual In-Line
NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH.
-B1 8
3. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL. 4. DIM F MAY NARROW TO 0.76 (0.030) WHERE THE LEAD ENTERS THE CERAMIC BODY.
C
L
5. 620 01 THRU 08 OBSOLETE, NEW STANDARD 620 09.
-TSEATING PLANE
K E F D 16 PL
0.25 (0.010)
M
N G
T A
S
M J 16 PL
0.25 (0.010)
M
T
B
S
DIM A B C D E F G J K L M N
MILLIMETERS MIN MAX
19.05 6.10 19.55 7.36 4.19 0.39 0.53
INCHES MIN MAX
0.750 0.240 0.770 0.290 0.165 0.015 0.021
1.27 BSC 1.40 1.77
0.050 BSC 0.055 0.070
2.54 BSC 0.23 0.27 5.08 7.62 BSC 0 0.39 15 0.88
0.100 BSC 0.009 0.011 0.200 0.300 BSC 0 0.015 15 0.035
FAST AND LS TTL DATA 5-250
Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. "Typical" parameters can and do vary in different applications. All operating parameters, including "Typicals" must be validated for each customer application by customer's technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer.
Literature Distribution Centers: USA: Motorola Literature Distribution; P.O. Box 20912; Phoenix, Arizona 85036. EUROPE: Motorola Ltd.; European Literature Centre; 88 Tanners Drive, Blakelands, Milton Keynes, MK14 5BP, England. JAPAN: Nippon Motorola Ltd.; 4-32-1, Nishi-Gotanda, Shinagawa-ku, Tokyo 141, Japan. ASIA PACIFIC: Motorola Semiconductors H.K. Ltd.; Silicon Harbour Center, No. 2 Dai King Street, Tai Po Industrial Estate, Tai Po, N.T., Hong Kong.
FAST AND LS TTL DATA 5-251

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