Fairchild Semiconductor DM74ALS373WMX, DM74ALS373WM, DM74ALS373SJX, DM74ALS373SJ, DM74ALS373N Datasheet

April 1984

Revised February 2000

DM74ALS373

Octal D-Type 3-STATE Transparent Latch

General Description

These 8-bit registers feature totem-pole 3-STATE outputs designed specifically for driving highly-capacitive or relatively low-impedance loads. The high-impedance state and increased high-logic-level drive provide these registers with the capability of being connected directly to and driving the bus lines in a bus-organized system without need for interface or pull-up components. They are particularly attractive for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.

The eight latches of the DM74ALS373 are transparent D- type latches. While the enable (G) is HIGH the Q outputs will follow the data (D) inputs. When the enable is taken LOW the output will be latched at the level of the data that was set up.

A buffered output control input can be used to place the eight outputs in either a normal logic state (HIGH or LOW logic levels) or a high-impedance state. In the high-imped- ance state the outputs neither load nor drive the bus lines significantly.

The output control does not affect the internal operation of the latches. That is, the old data can be retained or new data can be entered even while the outputs are OFF.

Features

■Switching specifications at 50 pF

■Switching specifications guaranteed over full temperature and VCC range

■Advanced oxide-isolated, ion-implanted Schottky TTL process

■Functionally and pin for pin compatible with LS TTL counterpart

■Improved AC performance over DM74LS373 at approximately half the power

■3-STATE buffer-type outputs drive bus lines directly

Ordering Code:

Order Number	Package Number	Package Description
DM74ALS373WM	M20B	20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74ALS373SJ	M20D	20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74ALS373N	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 Diagram

Latch Transparent STATE-3 Type-D Octal DM74ALS373

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DM74ALS373

Function Table							Logic Diagram
		Output		Enable	D	Output
	Control			G		Q
		L		H	H	H
		L		H	L	L
		L		L	X	Q0
		H		X	X	Z

L = LOW State

H = HIGH State

X = Don’t Care

Z = High Impedance State

Q0 = Previous Condition of Q

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Absolute Maximum Ratings(Note 1)

Supply Voltage	7V
Input Voltage	7V
Voltage Applied to Disabled Output	5.5V
Operating Free Air Temperature Range	0°C to +70°C
Storage Temperature Range	−65°C to +150°C
Typical θJA
N Package	57.0°C/W
M Package	76.0°C/W

Note 1: The “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum ratings. The “Recommended Operating Conditions” table will define the conditions for actual device operation.

Recommended Operating Conditions

Symbol	Parameter	Min	Nom	Max	Units
VCC	Supply Voltage	4.5	5	5.5	V
VIH	HIGH Level Input Voltage	2			V
VIL	LOW Level Input Voltage			0.8	V
IOH	HIGH Level Output Current			−2.6	mA
IOL	LOW Level Output Current			24	mA
tW	Width of Enable Pulse, HIGH or LOW	10			ns
tSU	Data Setup Time (Note 2)	10↓			ns
tH	Data Hold Time (Note 2)	7↓			ns
TA	Free Air Operating Temperature	0		70	°C

Note 2: The (↓) arrow indicates the negative edge of the enable is used for reference.

Electrical Characteristics

over recommended operating free air temperature range. All typical values are measured at VCC = 5V, TA = 25°C.

Symbol	Parameter	Conditions		Min	Typ	Max	Units
VIK	Input Clamp Voltage	VCC = 4.5V, II = −18 mA				−1.5	V
VOH	HIGH Level	VCC = 4.5V	IOH = −2.6 mA	2.4	3.3		V
	Output Voltage	VCC = 4.5V to 5.5V		VCC − 2			V
		IOH = −400 μA
VOL	LOW Level	VCC = 4.5V	IOL = 24 mA		0.35	0.5	V
	Output Voltage
II	Input Current at Maximum	VCC = 5.5V				0.1	mA
	Input Voltage	VIH = 7V
IIH	HIGH Level Input Current	VCC = 5.5V, VIH = 2.7V				20	μA
IIL	LOW Level Input Current	VCC = 5.5V, VIL = 0.4V				−0.1	mA
IO	Output Drive Current	VCC = 5.5V	VO = 2.25V	−30		−112	mA
IOZH	OFF-State Output Current	VCC = 5.5V				20	μA
	HIGH Level Voltage Applied	VO = 2.7V
IOZL	OFF-State Output Current	VCC = 5.5V				−20	μA
	LOW Level Voltage Applied	VO = 0.4V
ICC	Supply Current	VCC = 5.5V	Outputs HIGH		9	16	mA
		Outputs OPEN	Outputs LOW		16	25	mA
			Outputs Disabled		17	27	mA

DM74ALS373

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