Fairchild Semiconductor DM74LS240WMX, DM74LS240WM, DM74LS240SJX, DM74LS240SJ, DM74LS240N Datasheet

August 1986

Revised March 2000

DM74LS240 • DM74LS241

Octal 3-STATE Buffer/Line Driver/Line Receiver

General Description

These buffers/line drivers are designed to improve both the performance and PC board density of 3-STATE buffers/ drivers employed as memory-address drivers, clock drivers, and bus-oriented transmitters/receivers. Featuring 400 mV of hysteresis at each low current PNP data line input, they provide improved noise rejection and high fanout outputs and can be used to drive terminated lines down to 133Ω.

Features

■3-STATE outputs drive bus lines directly

■PNP inputs reduce DC loading on bus lines

■Hysteresis at data inputs improves noise margins

■Typical IOL (sink current)

24mA

■Typical IOH (source current)

−15 mA

■ Typical propagation delay times

Inverting	10.5 ns
Noninverting	12 ns

■Typical enable/disable time 18 ns

■Typical power dissipation (enabled)

Inverting	130 mW
Noninverting	135 mW

Ordering Code:

Order Number	Package Number	Package Description
DM74LS240WM	M20B	20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74LS240SJ	M20D	20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74LS240N	N20A	20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
DM74LS241WM	M20B	20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74LS241N	N20A	20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code.

Connection Diagrams

DM74LS240	DM74LS241

Receiver Driver/Line Buffer/Line STATE-3 Octal DM74LS241 • DM74LS240

© 2000 Fairchild Semiconductor Corporation

DS006411

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DM74LS240 • DM74LS241

Function Tables

DM74LS240

			Inputs			Output
	G				A	Y
		L			L	H
		L			H	L
		H			X	Z
L = LOW Logic Level
H = HIGH Logic Level
X = Either LOW or HIGH Logic Level
Z = High Impedance

DM74LS241

			Inputs			Outputs
G		G		1A	2A	1Y	2Y
X		L		L	X	L
X		L		H	X	H
X		H		X	X	Z
H		X		X	L		L
H		X		X	H		H
L		X		X	X		Z

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2

Absolute Maximum Ratings(Note 1)

	Supply Voltage	7V	Note 1: The “Absolute Maximum Ratings” are those values beyond which
			the safety of the device cannot be guaranteed. The device should not be
	Input Voltage	7V	operated at these limits. The parametric values defined in the Electrical
			Characteristics tables are not guaranteed at the absolute maximum ratings.
	Operating Free Air Temperature Range	0°C to +70°C
			The “Recommended Operating Conditions” table will define the conditions
	Storage Temperature Range	−65°C to +150°C	for actual device operation.

Recommended Operating Conditions

Symbol	Parameter	Min	Nom	Max	Units
VCC	Supply Voltage	4.75	5	5.25	V
VIH	HIGH Level Input Voltage	2			V
VIL	LOW Level Input Voltage			0.8	V
IOH	HIGH Level Output Current			−15	mA
IOL	LOW Level Output Current			24	mA
TA	Free Air Operating Temperature	0		70	°C

Electrical Characteristics

over recommended operating free air temperature range (unless otherwise noted)

Symbol	Parameter	Conditions			Min	Typ	Max	Units
						(Note 2)
VI	Input Clamp Voltage	VCC = Min, II = −18 mA					−1.5	V
HYS	Hysteresis (VT+ − VT−)	VCC = Min			0.2	0.4		V
	Data Inputs Only
VOH	HIGH Level Output Voltage	VCC = Min, VIH = Min			2.7
		VIL = Max, IOH = −1 mA
		VCC = Min, VIH = Min			2.4	3.4		V
		VIL = Max, IOH = −3 mA
		VCC = Min, VIH = Min			2
		VIL = 0.5V, IOH = Max
VOL	LOW Level Output Voltage	VCC = Min	IOL = 12 mA				0.4
		VIL = Max	IOL	= Max			0.5	V
		VIH = Min
IOZH	Off-State Output Current,	VCC = Max	VO	= 2.7V			20	μA
	HIGH Level Voltage Applied	VIL = Max
IOZL	Off-State Output Current,	VIH = Min	VO	= 0.4V			−20	μA
	LOW Level Voltage Applied
II	Input Current at Maximum	VCC = Max					0.1	mA
	Input Voltage	VI = 7V
IIH	HIGH Level Input Current	VCC = Max, VI = 2.7V					20	μA
IIL	LOW Level Input Current	VCC = Max, VI = 0.4V					−0.2	mA
IOS	Short Circuit Output Current	VCC = Max (Note 3)			−40		−225	mA
ICC	Supply Current	VCC = Max,	Outputs HIGH			13	23
		Outputs OPEN	Outputs LOW			26	44
						27	46	mA
			Outputs Disabled			29	50
						32	54
Note 2: All	typicals are at VCC = 5V, TA = 25°C.

Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.

DM74LS241 • DM74LS240

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