Motorola MC74LCX138MEL, MC74LCX138SD, MC74LCX138M, MC74LCX138D, MC74LCX138DR2 Datasheet

MOTOROLA

SEMICONDUCTOR TECHNICAL DATA

Low-Voltage CMOS 1-of-8

Decoder/Demultiplexer

With 5V-Tolerant Inputs

The MC74LCX138 is a high performance, 1±of±8 decoder/ demultiplexer operating from a 2.7 to 3.6V supply. High impedance TTL compatible inputs significantly reduce current loading to input drivers while TTL compatible outputs offer improved switching noise performance. A VI specification of 5.5V allows MC74LCX138 inputs to be safely driven from 5V devices. The MC74LCX138 is suitable for memory address decoding and other TTL level bus oriented applications.

The MC74LCX138 high±speed 1±of±8 decoder/demultiplexer accepts three binary weighted inputs (A0, A1, A2) and, when enabled, provides eight mutually exclusive active±LOW outputs (O0±O7). The LCX138 features three Enable inputs, two active±LOW (E1, E2) and one active±HIGH (E3). All outputs will be HIGH unless E1 and E2 are LOW, and E3 is HIGH. This multiple enabled function allows easy parallel expansion of the device to a 1±of±32 (5 lines to 32 lines) decoder with just four LCX138 devices and one inverter (See Figure 1). The LCX138 can be used as an 8±output demultiplexer by using one of the active±LOW Enable inputs as the data input and the other Enable inputs as strobes. The Enable inputs which are not used must be permanently tied to their appropriate active±HIGH or active±LOW state.

Current drive capability is 24mA at the outputs.

•Designed for 2.7 to 3.6V VCC Operation

•5V Tolerant Inputs Ð Interface Capability With 5V TTL Logic

•LVTTL Compatible

•LVCMOS Compatible

•24mA Balanced Output Sink and Source Capability

•Near Zero Static Supply Current (10μA) Substantially Reduces System Power Requirements

•Latchup Performance Exceeds 500mA

•ESD Performance: Human Body Model >2000V; Machine Model >200V

Pinout: 16±Lead Plastic Package (Top View)

VCC		O0		O1		O2		O3		O4		O5		O6
16		15		14		13		12		11		10		9

	1		2		3		4			5			6		7			8
	A0		A1		A2		E1			E2			E3		O7		GND

MC74LCX138

LOW±VOLTAGE CMOS DECODER/DEMULTIPLEXER

		D SUFFIX
16		PLASTIC SOIC
	1	CASE 751B±05
		M SUFFIX
16		PLASTIC SOIC EIAJ
	1	CASE 966±01
16		SD SUFFIX
		PLASTIC SSOP
	1	CASE 940B±03
		DT SUFFIX
16		PLASTIC TSSOP
	1	CASE 948F±01

PIN NAMES

	Pins				Function
	A0±A2				Address Inputs
	E1±E2				Enable Inputs
	E3				Enable Input
	O0±O7				Outputs

11/96

Motorola, Inc. 1996 1 REV 1

MC74LCX138

LOGIC DIAGRAM

A2						A1						A0													E1					E2					E3
		3					2						1														4				5					6

	7			9			10			11			12			13			14			15
O7			O6			O5			O4			O3			O2			O1			O0

INPUTS

OUTPUTS

E1

E2

E3

A0

A1

A2

O0

O1

O2

O3

O4

O5

O6

O7

H

X

X

X

X

X

H

H

H

H

H

H

H

H

X

H

X

X

X

X

H

H

H

H

H

H

H

H

X

X

L

X

X

X

H

H

H

H

H

H

H

H

L

L

H

L

L

L

L

H

H

H

H

H

H

H

L

L

H

H

L

L

H

L

H

H

H

H

H

H

L

L

H

L

H

L

H

H

L

H

H

H

H

H

L

L

H

H

H

L

H

H

H

L

H

H

H

H

L

L

H

L

L

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

L

H

H

H

H

H

H

H

H

L

H

L

L

H

H

H

H

H

H

H

H

H

H

H

L

H = High Voltage Level; L = Low Voltage Level; X = High or Low Voltage Level and Transitions Are Acceptable; For ICC reasons, DO NOT FLOAT Inputs

A0
A1
A2							`04
A3
A4	H
	123		123		123		123
A0 A1 A2	E	A0 A1 A2	E	A0 A1 A2	E	A0 A1 A2	E
O0 O1 O2 O3 O4 O5 O6 O7		O0 O1 O2 O3 O4 O5 O6 O7		O0 O1 O2 O3 O4 O5 O6 O7		O0 O1 O2 O3 O4 O5 O6 O7
O0							O31

Figure 1. Expansion to 1±of±32 Decoding

MOTOROLA

2

LCX DATA

BR1339 Ð REV 3

				MC74LCX138
ABSOLUTE MAXIMUM RATINGS*
Symbol	Parameter	Value	Condition		Unit
VCC	DC Supply Voltage	±0.5 to +7.0			V
VI	DC Input Voltage	±0.5 ≤ VI ≤ +7.0			V
VO	DC Output Voltage	±0.5 ≤ VO ≤ VCC + 0.5	Note 1.		V
IIK	DC Input Diode Current	±50	VI < GND		mA
IOK	DC Output Diode Current	±50	VO < GND		mA
		+50	VO > VCC		mA
IO	DC Output Source/Sink Current	±50			mA
ICC	DC Supply Current Per Supply Pin	±100			mA
IGND	DC Ground Current Per Ground Pin	±100			mA
TSTG	Storage Temperature Range	±65 to +150			°C

* Absolute maximum continuous ratings are those values beyond which damage to the device may occur. Exposure to these conditions or conditions beyond those indicated may adversely affect device reliability. Functional operation under absolute±maximum±rated conditions is not implied.

1. Output in HIGH or LOW State. IO absolute maximum rating must be observed.

RECOMMENDED OPERATING CONDITIONS

Symbol	Parameter		Min	Typ	Max	Unit
VCC	Supply Voltage	Operating	2.0	3.3	3.6	V
		Data Retention Only	1.5	3.3	3.6
VI	Input Voltage		0		5.5	V
VO	Output Voltage	(HIGH or LOW State)	0		VCC	V
IOH	HIGH Level Output Current, VCC = 3.0V ± 3.6V				±24	mA
IOL	LOW Level Output Current, VCC = 3.0V ± 3.6V				24	mA
IOH	HIGH Level Output Current, VCC = 2.7V ± 3.0V				±12	mA
IOL	LOW Level Output Current, VCC = 2.7V ± 3.0V				12	mA
TA	Operating Free±Air Temperature		±40		+85	°C
t/ V	Input Transition Rise or Fall Rate, VIN from 0.8V to 2.0V,		0		10	ns/V
	VCC = 3.0V

LCX DATA	3	MOTOROLA
BR1339 Ð REV 3