Motorola MC74F544DW, MC74F544N Datasheet

4-216

FAST AND LS TTL DATA

OCTAL REGISTERED
TRANSCEIVER, INVERTING,
3-STATE

The MC74F544 Octal Registered Transceivers contain two sets of D-T ype
latches for temporary storage of data flowing in either direction. Separate
Latch Enable (LEAB, LEBA) and Enable (OEAB, OEBA) inputs are provided
for each register to permit independent control of inputting and outputting in
either direction of data flow. The MC74F544 has an inverting data path. The
A outputs are guaranteed to sink 24 mA while the B outputs are rated for
64 mA.

• Combines 74F245 and 74F373 Type Functions in One Chip

• 8-Bit Octal Transceiver

• Inverting

• Back-to-Back Registers for Storage

• Separate Controls for Data Flow in Each Direction

• Glitchless Outputs During 3-State Power Up or Power Down Operation

• High Impedance Outputs in Power Off State

• A Outputs Sink 24 mA and Source 3.0 mA

• B Outputs Sink 64 mA and Source 15 mA

• See F543 for Noninverting Version

• ESD Protection > 4000 Volts

PIN ASSIGNMENT

18 17 16 15 14 13

1 2 3 4 5 6

7

20 19

8

B2

LEBA

B3 B4 B5 B6 LEABB7 OEAB

OEBA A0 A2 A3 A4 A5 A6

9 10

A7

A1

11 12

22 2124 23

VCCEBA

B0 B1

EAB GND

GUARANTEED OPERATING RANGES

Symbol Parameter Min Typ Max Unit

V

CC

DC Supply Voltage 74 4.5 5.0 5.5 V

T

A

Operating Ambient Temperature Range 74 0 25 70 °C

I

OH

Output Current — High 74 — — –3.0/–15 mA

I

OL

Output Current — Low 74 — — 24/64 mA

MC74F544

OCTAL REGISTERED

TRANSCEIVER, INVERTING,

3-STATE

FAST SCHOTTKY TTL

ORDERING INFORMATION

MC74FXXXN Plastic
MC74FXXXDW SOIC

N SUFFIX

PLASTIC

CASE 724-03

DW SUFFIX

SOIC

CASE 751E-03

24

1

24

1

4-217

FAST AND LS TTL DATA

MC74F544

FUNCTION TABLE

Inputs

OEXX EXX LEXX Data

Outputs

Status

H X X X Z Outputs disabled
X H X X Z Outputs disabled
L

L

↑
↑

L
L

l

h

Z
Z

Outputs disabled
Data latched

L
L

L
L

↑
↑

l

h

H
L

Data latched

L
L

L
L

L
L

L
H

H
L

Transparent

L L H X NC Hold

H = HIGH voltage level: h = HIGH state must be present one set-up time before the LOW-to-HIGH transition of LEXX or EXX (XX = AB or BA): L = LOW voltage level:

l = LOW state must be present one set-up time before the LOW-to-HIGH transition of LEXX

or EXX (XX = AB or BA): X = Don’t care: Z = HIGH impedance state:

NC = No Change.

FUNCTIONAL DESCRIPTION

The MC74F544 contains two sets of eight D-type latches,
with separate input and controls for each set. For data flow
from A to B, for example, the A-to-B Enable (EAB

) input must

be LOW in order to enter data from A0

–A7 or take data from

B0

–B7, as indicated in the Function Table. With EAB LOW,

a LOW signal on the A-to-B latch enable (LEAB

) input makes

the A-to-B latches transparent; a subsequent LOW-to-HIGH

transition of the LEAB

signal puts the A latches in the storage
mode and their outputs no longer change with the A inputs.
With EAB

and OEAB both LOW, the 3-State B output buffers
are active and reflect the inverted data present at the output
of the A latches. Control of data flow from B to A is similar, but
using the EBA

, LEBA, and OEBA inputs.

DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE

(unless otherwise specified)

Limits

Test Conditions

Symbol

Parameter

Min Typ Max

Unit

Test Conditions

(Note 1)

V

IH

Input HIGH Voltage 2.0 — — V Guaranteed Input HIGH Voltage

V

IL

Input LOW Voltage — — 0.8 V Guaranteed Input LOW Voltage

V

IK

Input Clamp Diode Voltage — –0.73 –1.2 V VCC = MIN, IIN = –18 mA

2.4 — —

VCC = 4.5 V

V

OH

Output HIGH Voltage

A0–A7

74

2.7 3.4 —

V

IOH = –3.0 mA

VCC = 4.75 V

OH

B0–B7 74 2.0 — — V IOH = –15 mA VCC = 4.5 V
A0–A7 74 — 0.35 0.5 V IOL = 24 mA

VOLOutput LOW Voltage

B0–B7 74 — 0.4 0.55 V IOL = 64 mA

VCC = MIN

I/O Pins — — 1.0 mA VCC = MAX, VIN = 5.5 V

Control Pins — — 100 µA VCC = MAX, VIN = 7.0 V

IIHInput HIGH Current

Control Pins — — 20 µA

I/O Pins — — 70 µA

VCC = MAX, VIN = 2.7 V

EAB, EBA — — –1.2

IILInput LOW Current

Other Inputs — — –0.6

mA

VCC = MAX, VIN = 0.5 V

I

OZH

Off-State Output Current — — 70 µA VCC = MAX, V

OUT

= 2.7 V

I

OZL

Off-State Output Current,
Low-Level Voltage Applied

— — –600 µA VCC = MAX, V

OUT

= 0.5 V

A

n

Outputs

–60 — –150

IOSOutput Short Circuit Current (Note 2)

B

n

Outputs

–100 — –225

mA

VCC = MAX, V

OUT

= 0 V

I

CCH

— 70 105

I

CC

Total Supply Current

I

CCL

— 95 130

mA VCC = MAX

CC

I

CCZ

— 95 125

CC

= MAX

NOTES:

1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable device type.

2. Not more than one output should be shorted at a time, nor for more than 1 second.