FAIRCHILD MM74HC245A

Revised May 2005
MM74HC245A
Octal 3-STATE Transceiver
General Description
Features
The MM74HC245A 3-STATE bidirectional buffer utilizes
advanced silicon-gate CMOS technology, and is intended
for two-way asynchronous communication between data
buses. It has high drive current outputs which enable high
speed operation even when driving large bus capacitances. This circuit possesses the low power consumption
and high noise immunity usually associated with CMOS circuitry, yet has speeds comparable to low power Schottky
TTL circuits.
■ Typical propagation delay: 13 ns
■ Wide power supply range: 2–6V
■ Low quiescent current: 80 PA maximum (74 HC)
■ 3-STATE outputs for connection to bus oriented systems
■ High output drive: 6 mA (minimum)
■ Same as the 645
This device has an active LOW enable input G and a direction control input, DIR. When DIR is HIGH, data flows from
the A inputs to the B outputs. When DIR is LOW, data flows
from the B inputs to the A outputs. The MM74HC245A
transfers true data from one bus to the other.
This device can drive up to 15 LS-TTL Loads, and does not
have Schmitt trigger inputs. All inputs are protected from
damage due to static discharge by diodes to VCC and
ground.
Ordering Code:
Order Number
Package Number
MM74HC245AWM
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
M20D
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
MM74HC245ASJ
MM74HC245AMTC
MM74HC245AN
MTC20
N20A
Package Description
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
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
Truth Table
Pin Assignments for DIP, SOIC, SOP and TSSOP
Control
Inputs
G
Operation
DIR
L
L
B data to A bus
L
H
A data to B bus
H
X
Isolation
H HIGH Level
L LOW Level
X Irrelevant
Top View
© 2005 Fairchild Semiconductor Corporation
DS005165
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MM74HC245A Octal 3-STATE Transceiver
September 1983
MM74HC245A
Logic Diagram
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Recommended Operating
Conditions
Supply Voltage (VCC)
DC Input Voltage DIR and G pins (VIN)
DC Input/Output Voltage (VIN , VOUT)
Clamp Diode Current (ICD)
DC Output Current, per pin (IOUT)
DC VCC or GND Current, per pin (ICC)
Storage Temperature Range (TSTG)
0.5 to 7.0V
1.5 to VCC 1.5V
0.5 to VCC 0.5V
r20 mA
r35 mA
r70 mA
65qC to 150qC
Supply Voltage (VCC)
600 mW
S.O. Package only
500 mW
(VIN, VOUT)
Operating Temperature Range (TA)
(tr, tf)
Symbol
VIH
VIL
VOH
Parameter
VCC
V
85
qC
VCC
2.0V
1000
ns
VCC
4.5V
500
ns
VCC
6.0V
400
ns
Note 2: Unless otherwise specified all voltages are referenced to ground.
Note 3: Power Dissipation temperature derating — plastic “N” package: 12 mW/qC from 65qC to 85qC.
VCC
TA
25qC
Typ
TA
40 to 85qC TA 55 to 125qC
Guaranteed Limits
Units
Minimum HIGH Level Input
2.0V
1.5
1.5
1.5
V
Voltage
4.5V
3.15
3.15
3.15
V
V
6.0V
4.2
4.2
4.2
Maximum LOW Level Input
2.0V
0.5
0.5
0.5
V
Voltage
4.5V
1.35
1.35
1.35
V
6.0V
1.8
1.8
1.8
V
Minimum HIGH Level Output
VIN
Voltage
|IOUT| d 20 PA
VIH or VIL
2.0V
2.0
1.9
1.9
1.9
V
4.5V
4.5
4.4
4.4
4.4
V
6.0V
6.0
5.9
5.9
5.9
V
|IOUT| d 6.0 mA
4.5V
4.2
3.98
3.84
3.7
V
|IOUT| d 7.8 mA
6.0V
5.7
5.48
5.34
5.2
V
VIH or VIL
Maximum LOW Level Output
VIN
Voltage
|IOUT| d 20 PA
Input Leakage
VIH or VIL
2.0V
0
0.1
0.1
0.1
V
4.5V
0
0.1
0.1
0.1
V
6.0V
0
0.1
0.1
0.1
V
|IOUT| d 6.0 mA
4.5V
0.2
0.26
0.33
0.4
V
|IOUT| d 7.8 mA
6.0V
0.2
0.26
0.33
0.4
V
VIN
6.0V
r0.1
r1.0
r1.0
PA
6.0V
r0.5
r5.0
r10
PA
6.0V
8.0
80
160
PA
VIN
IIN
0
40
(Note 4)
Conditions
VIN
VOL
V
Note 1: Maximum Ratings are those values beyond which damage to the
device may occur.
260qC
DC Electrical Characteristics
Units
6
Input Rise/Fall Times
Lead Temperature (TL)
(Soldering 10 seconds)
Max
2
DC Input or Output Voltage
Power Dissipation (PD)
(Note 3)
Min
VIH or VIL
VCC to GND
Current (G and DIR)
IOZ
ICC
Maximum 3-STATE Output
VOUT
Leakage Current
Enable G
Maximum Quiescent Supply
VIN
Current
IOUT
VCC or GND
VIH
VCC or GND
0 PA
Note 4: For a power supply of 5V r10% the worst case output voltages (VOH, and VOL) occur for HC at 4.5V. Thus the 4.5V values should be used when
designing with this supply. Worst case VIH and VIL occur at VCC 5.5V and 4.5V respectively. (The VIH value at 5.5V is 3.85V.) The worst case leakage current (IIN, ICC, and IOZ) occur for CMOS at the higher voltage and so the 6.0V values should be used.
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MM74HC245A
Absolute Maximum Ratings(Note 1)
(Note 2)
MM74HC245A
AC Electrical Characteristics
VCC
25qC, tr
5V, TA
Symbol
tf 6ns
Parameter
Conditions
Guaranteed
Typ
Units
Limit
tPHL, tPLH
Maximum Propagation Delay
CL
45 pF
12
17
ns
tPZH, tPZL
Maximum Output Enable
RL
1 k:
24
35
ns
Time
CL
45 pF
Maximum Output Disable
RL
1 k:
18
25
ns
Time
CL
5 pF
tPHZ, tPLZ
AC Electrical Characteristics
VCC
2.0V to 6.0V, CL
Symbol
50 pF, tr
tf 6ns (unless otherwise specified)
Parameter
Conditions
VCC
TA
25qC
Typ
TA
40 to 85qC TA 55 to 125qC
Units
Guaranteed Limits
tPHL,
Maximum Propagation
CL
50 pF
2.0V
31
90
113
135
ns
tPLH
Delay
CL
150 pF
2.0V
41
96
116
128
ns
CL
50 pF
4.5V
13
18
23
27
ns
CL
150 pF
4.5V
17
22
28
33
ns
CL
50 pF
6.0V
11
15
19
23
ns
CL
150 pF
6.0V
14
19
23
28
ns
tPZH,
Maximum Output Enable
RL
1 k:
tPZL
Time
CL
50 pF
2.0V
71
190
240
285
ns
CL
150 pF
2.0V
81
240
300
360
ns
CL
50 pF
4.5V
26
38
48
57
ns
CL
150 pF
4.5V
31
48
60
72
ns
CL
50 pF
6.0V
21
32
41
48
ns
CL
150 pF
6.0V
25
41
51
61
ns
tPHZ,
Maximum Output Disable
RL
1 k:
2.0V
39
135
169
203
ns
tPLZ
Time
CL
50 pF
4.5V
20
27
34
41
ns
ns
tTLH, tTHL Output Rise and Fall Time
CL 50 pF
6.0V
18
23
29
34
2.0V
20
60
75
90
ns
4.5V
6
12
15
18
ns
5
10
13
15
6.0V
CPD
Power Dissipation
G
VIL
Capacitance (Note 5)
G
VIH
50
ns
pF
5
pF
CIN
Maximum Input Capacitance
5
10
10
10
pF
CIN/OUT
Maximum Input/Output
15
20
20
20
pF
Capacitance, A or B
Note 5: CPD determines the no load dynamic power consumption, PD CPD VCC2 fICC VCC, and the no load dynamic current consumption, IS CPD VCC fICC.
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MM74HC245A
Physical Dimensions inches (millimeters) unless otherwise noted
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
Package Number M20B
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MM74HC245A
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
Package Number M20D
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MM74HC245A
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
Package Number MTC20
7
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MM74HC245A Octal 3-STATE Transceiver
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
Package Number N20A
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
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FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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