Texas Instruments JM38510-33701BFA, JM38510-33701B2A, JM38510-33701BEA, SN54F138J, SN74F138D Datasheet

							SN54F138, SN74F138
3-LINE TO 8-LINE DECODERS/DEMULTIPLEXERS
		SDFS051B ± MARCH 1987 ± REVISED JULY 1996
D Designed Specifically for High-Speed	SN54F138 . . . J PACKAGE
Memory Decoders and Data Transmission	SN74F138 . . . D OR N PACKAGE
Systems				(TOP VIEW)
D Incorporates Three Enable Inputs to			A			1	16		VCC
Simplify Cascading and/or Data Reception
			B			2	15		Y0
D Package Options Include Plastic
			C			3	14		Y1
Small-Outline Packages, Ceramic Chip		G2A				4	13		Y2
Carriers, and Standard Plastic and Ceramic									Y3
		G2B				5	12
300-mil DIPs		G1				6	11		Y4
description		Y7				7	10		Y5
	GND					8	9		Y6

	The	′F138	is	designed to be used in
	high-performance			memory-decoding or data-	SN54F138 . . . FK PACKAGE
	routing applications requiring very short						(TOP VIEW)
	propagation		delay times. In high-performance					NC	CC
	memory systems, these decoders can be used to					B	A
									V Y0
	minimize the effects of system decoding. When					3	2	1	20 19
	employed with high-speed memories utilizing a				C					Y1
						4			18
	fast enable circuit, the delay times of this decoder
					G2A	5			17	Y2
	and the enable time of the memory are usually
					NC	6			16	NC
	less than the typical access time of the memory.
					G2B	7			15	Y3
	This	means	that	the effective system delay
					G1	8			14	Y4
	introduced by the decoder is negligible.
						9	10 11 12 13

	The conditions at the binary-select inputs and the	Y7 GND NC Y6 Y5
	three enable inputs select one of eight output
	lines. Two active-low and one active-high enable	NC ± No internal connection
	inputs reduce the need for external gates or
	inverters when expanding. A 24-line decoder can

be implemented without external inverters and a 32-line decoder requires only one inverter. An enable input can be used as a data input for demultiplexing applications.

The SN54F138 is characterized for operation over the full military temperature range of ±55°C to 125°C. The SN74F138 is characterized for operation from 0°C to 70°C.

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 of this 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.

Copyright 1996, Texas Instruments Incorporated

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

1

SN54F138, SN74F138

3-LINE TO 8-LINE DECODERS/DEMULTIPLEXERS

SDFS051B ± MARCH 1987 ± REVISED JULY 1996

FUNCTION TABLE

ENABLE INPUTS

SELECT INPUTS

OUTPUTS

G1

C

B

A

Y0

Y1

Y2

Y3

Y4

Y5

Y6

Y7

G2A

G2B

X

H

X

X

X

X

H

H

H

H

H

H

H

H

X

X

H

X

X

X

H

H

H

H

H

H

H

H

L

X

X

X

X

X

H

H

H

H

H

H

H

H

H

L

L

L

L

L

L

H

H

H

H

H

H

H

H

L

L

L

L

H

H

L

H

H

H

H

H

H

H

L

L

L

H

L

H

H

L

H

H

H

H

H

H

L

L

L

H

H

H

H

H

L

H

H

H

H

H

L

L

H

L

L

H

H

H

H

L

H

H

H

H

L

L

H

L

H

H

H

H

H

H

L

H

H

H

L

L

H

H

L

H

H

H

H

H

H

L

H

H

L

L

H

H

H

H

H

H

H

H

H

H

L

logic symbols (alternatives)²

1						BIN/OCT		0	15	Y0	1					DMUX		0	15	Y0
		A			1							A			0
2									14		2						0		14
		B			2			1		Y1		B				G	7	1		Y1
									13										13
3											3
		C			4			2	12	Y2		C			2			2	12	Y2
								3		Y3								3		Y3
6						&			11		6				&				11
	G1							4		Y4	G1							4		Y4
				4			EN		10					4					10
	G2A							5		Y5	G2A							5		Y5
		5						6	9	Y6		5						6	9	Y6
G2B									7		G2B								7
								7		Y7								7		Y7

² These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.

2	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265