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SN54147, SN54148, SN54LS147, SN54LS148 SN74147, SN74148 (TIM9907), SN74LS147, SN74LS148 10 LINE TO 4 LINE AND 8 LINE TO 3 LINE PRIORITY ENCODERS
SDLS053B − OCTOBER 1976 − REVISED MAY 2004

D D

’147, ’LS147 Encode 10-Line Decimal to 4-Line BCD Applications Include: − Keyboard Encoding − Range Selection

D D

’148, ’LS148 Encode 8 Data Lines to 3-Line Binary (Octal) Applications Include:− n-Bit Encoding − Code Converters and Generators

SN54147, SN54LS147 . . . J OR W PACKAGE SN74147, SN74LS147 . . . D OR N PACKAGE (TOP VIEW)

SN54148, SN54LS148 . . . J OR W PACKAGE SN74148, SN74LS148 . . . D, N, OR NS PACKAGE (TOP VIEW)

4 5 6 7 8 C B GND

1 2 3 4 5 6 7 8

16 15 14 13 12 11 10 9

VCC NC D 3 2 1 9 A

4 5 6 7 EI A2 A1 GND

1 2 3 4 5 6 7 8

16 15 14 13 12 11 10 9VCC E0 GS 3 2 1 0 A0

SN54LS147 . . . FK PACKAGE (TOP VIEW)

SN54LS148 . . . FK PACKAGE (TOP VIEW)

5 4 NC VCC NC

6 7 NC 8 C

4 5 6 7 8

3 2 1 20 19 18 17 16 15 14 9 10 11 12 13

5 4 NC VCC E0 D 3 NC 2 1 6 7 NC EI A2
4 5 6 7 8 3 2 1 20 19 18 17 16 15 14 9 10 11 12 13

GS 3 NC 2 1

B GND NC A 9

NC − No internal connection TYPICAL DATA DELAY 10 ns 10 ns 15 ns 15 ns TYPICALPOWER DISSIPATION 225 mW 190 mW 60 mW 60 mW

TYPE ’147 ’148 ’LS147 ’LS148

NOTE: The SN54147, SN54LS147, SN54148, SN74147, SN74LS147, and SN74148 are obsolete and are no longer supplied.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end ofthis data sheet.
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

A1 GND NC A0 0
On products compliant to MIL PRF 38535, all parameters are tested unless otherwisenoted. On all other products, production processing does not necessarily include testing of all parameters.

Copyright  2004, Texas Instruments Incorporated

1

SDLS053B − OCTOBER 1976 − REVISED MAY 2004

SN54147, SN54148, SN54LS147, SN54LS148 SN74147, SN74148 (TIM9907), SN74LS147, SN74LS148 10 LINE TO 4 LINE AND 8 LINE TO 3 LINE PRIORITY ENCODERS
description/ordering informationThese TTL encoders feature priority decoding of the inputs to ensure that only the highest-order data line is encoded. The ’147 and ’LS147 devices encode nine data lines to four-line (8-4-2-1) BCD. The implied decimal zero condition requires no input condition, as zero is encoded when all nine data lines are at a high logic level. The ’148 and ’LS148 devices encode 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. For all types, data inputs and outputs are active at the low logic level. All inputs are buffered to represent one normalized Series 54/74 or 54/74LS load, respectively. ORDERING INFORMATION
TA PDIP − N 0°C to 70°C SOIC − D SOP − NS CDIP− J −55 C 125°C −55°C to 125 C CFP − W PACKAGE† Tube Tube Tape and reel Tape and reel Tube Tube ORDERABLE PART NUMBER SN74LS148N SN74LS148D SN74LS148DR SN74LS148NSR SNJ54LS148J SNJ54LS148W LS148 74LS148 SNJ54LS148J SNJ54LS148W TOP-SIDE MARKING SN74LS148N

LCCC − FK Tube SNJ54LS148FK SNJ54LS148FK † Package drawings, standard packing quantities, thermal data, symbolization, and PCB designguidelines are available at www.ti.com/sc/package. FUNCTION TABLE − ’147, ’LS147 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 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 OUTPUTS 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

H = high logic...
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