74AC245 • 74ACT245 Octal Bidirectional Transceiver with 3-STATE
November 1988
Revised November 1999
74AC245 • 74ACT245
Octal Bidirectional Transceiver with 3-STATE
Inputs/Outputs
General Description
The AC/ACT245 contains eight non-inverting bidirectional
buffers with 3-STATE outputs and is intended for bus-ori-
ented applications. Current sinking capability is 24 mA at
both the A and B ports. The Transmit/Receive (T/R) input
determines the direction of data flow through the bidirec-
tional transceiver. Transmit (active-HIGH) enables data
from A ports to B ports; Receive (active-LOW) enables
data from B ports to A ports. The Output Enable input,
when HIGH, disables both A and B ports by placing them in
a HIGH Z condition.
Features
s
I
CC
and I
OZ
reduced by 50%
s
Noninverting buffers
s
Bidirectional data path
s
A and B outputs source/sink 24 mA
s
ACT245 has TTL-compatible inputs
Ordering Code:
Order Number
74AC245SC
74AC245SJ
74AC245MTC
74AC245PC
74ACT245SC
74ACT245SJ
74ACT245MSA
74ACT245MTC
74ACT245PC
Package Number
M20B
M20D
MTC20
N20A
M20B
M20D
MSA20
MTC20
N20A
Package Description
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300” Wide Body
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
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
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300” Wide Body
20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
20-Lead Shrink Small Outline Package (SSOP), EIAJ TYPE II, 5.3mm Wide
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
Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.
FACT is a trademark of Fairchild Semiconductor Corporation.
© 1999 Fairchild Semiconductor Corporation
DS009944
www.fairchildsemi.com
74AC245 • 74ACT245
Absolute Maximum Ratings
(Note 1)
Supply Voltage (V
CC
)
DC Input Diode Current (I
IK
)
V
I
= −0.5V
V
I
=
V
CC
+
0.5V
DC Input Voltage (V
I
)
DC Output Diode Current (I
OK
)
V
O
= −0.5V
V
O
=
V
CC
+
0.5V
DC Output Voltage (V
O
)
DC Output Source
or Sink Current (I
O
)
DC V
CC
or Ground Current
per Output Pin (I
CC
or I
GND
)
Storage Temperature (T
STG
)
Junction Temperature (T
J
)
PDIP
140°C
±50
mA
−65°C
to
+150°C
±50
mA
−20
mA
+20
mA
−0.5V
to V
CC
+
0.5V
−20
mA
+20
mA
−0.5V
to V
CC
+
0.5V
−0.5V
to
+7.0V
Recommended Operating
Conditions
Supply Voltage (V
CC
)
AC
ACT
Input Voltage (V
I
)
Output Voltage (V
O
)
Operating Temperature (T
A
)
Minimum Input Edge Rate (∆V/∆t)
AC Devices
V
IN
from 30% to 70% of V
CC
V
CC
@ 3.3V, 4.5V, 5.5V
Minimum Input Edge Rate (∆V/∆t)
ACT Devices
V
IN
from 0.8V to 2.0V
V
CC
@ 4.5V, 5.5V
125 mV/ns
Note 1:
Absolute maximum ratings are those values beyond which damage
to the device may occur. The databook specifications should be met, with-
out exception, to ensure that the system design is reliable over its power
supply, temperature, and output/input loading variables. Fairchild does not
recommend operation of FACT circuits outside databook specifications.
2.0V to 6.0V
4.5V to 5.5V
0V to V
CC
0V to V
CC
−40°C
to
+85°C
125 mV/ns
DC Electrical Characteristics for AC
Symbol
V
IH
Parameter
Minimum HIGH Level
Input Voltage
V
IL
Maximum LOW Level
Input Voltage
V
OH
Minimum HIGH Level
Output Voltage
V
CC
(V)
3.0
4.5
5.5
3.0
4.5
5.5
3.0
4.5
5.5
3.0
4.5
5.5
V
OL
Maximum LOW Level
Output Voltage
3.0
4.5
5.5
3.0
4.5
5.5
I
IN (Note 4)
I
OLD
I
OHD
I
OZT
Maximum Input Leakage Current
Dynamic Output
Current Minimum (Note 3)
Maximum I/O
Leakage Current
5.5
±
0.3
±
3.0
µA
5.5
5.5
5.5
5.5
4.0
0.002
0.001
0.001
T
A
= +25°C
Typ
1.5
2.25
2.75
1.5
2.25
2.75
2.99
4.49
5.49
2.1
3.15
3.85
0.9
1.35
1.65
2.9
4.4
5.4
2.56
3.86
4.86
0.1
0.1
0.1
0.36
0.36
0.36
±
0.1
T
A
= −40°C
to
+85°C
Guaranteed Limits
2.1
3.15
3.85
0.9
1.35
1.65
2.9
4.4
5.4
V
IN
=
V
IL
or V
IH
2.46
3.76
4.76
0.1
0.1
0.1
V
IN
=
V
IL
or V
IH
0.44
0.44
0.44
±
1.0
75
−75
40.0
µA
mA
mA
µA
V
I
OL
=
12 mA
I
OL
=
24 mA
I
OL
=
24 mA (Note 2)
V
I
=
V
CC
, GND
V
OLD
=
1.65V Max
V
OHD
=
3.85V Min
V
IN
=
V
CC
or GND
V
I
(OE)
=
V
IL
, V
IH
V
I
=
V
CC
, GND
V
O
=
V
CC
, GND
Note 2:
All outputs loaded; thresholds on input associated with output under test.
Note 3:
Maximum test duration 2.0 ms, one output loaded at a time.
Note 4:
I
IN
and I
CC
@ 3.0V are guaranteed to be less than or equal to the respective limit @ 5.5V V
CC
.
Units
Conditions
V
OUT
=
0.1V
V
or V
CC
−
0.1V
V
OUT
=
0.1V
V
or V
CC
−
0.1V
V
I
OUT
= −50 µA
I
OH
= −12
mA
V
I
OH
= −24
mA
I
OH
= −24
mA (Note 2)
V
I
OUT
=
50
µA
I
CC
(Note 4) Maximum Quiescent Supply Current
3
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74AC245 • 74ACT245
DC Characteristics for ACT
Symbol
V
IH
V
IL
V
OH
Parameter
Minimum HIGH Level
Input Voltage
Maximum LOW Level
Input Voltage
Minimum HIGH Level
Output Voltage
V
CC
(V)
4.5
5.5
4.5
5.5
4.5
5.5
4.5
5.5
V
OL
Maximum LOW Level
Output Voltage
4.5
5.5
4.5
5.5
I
IN
I
CCT
I
OLD
I
OHD
I
CC
I
OZT
Maximum Input
Leakage Current
Maximum
I
CC
/Input
Dynamic Output
Current Minimum (Note 6)
Maximum Quiescent
Supply Current
Maximum I/O
Leakage Current
5.5
±0.3
±3.0
µA
5.5
5.5
5.5
5.5
5.5
4.0
0.6
0.001
0.001
T
A
= +25°C
Typ
1.5
1.5
1.5
1.5
4.49
5.49
2.0
2.0
0.8
0.8
4.4
5.4
3.86
4.86
0.1
0.1
0.36
0.36
±0.1
T
A
= −40°C
to
+85°C
Guaranteed Limits
2.0
2.0
0.8
0.8
4.4
5.4
3.76
4.76
0.1
0.1
0.44
0.44
±1.0
1.5
75
−75
40.0
V
V
Units
V
V
V
Conditions
V
OUT
=
0.1V
or V
CC
−
0.1V
V
OUT
=
0.1V
or V
CC
−
0.1V
I
OUT
= −50 µA
V
IN
=
V
IL
or V
IH
I
OH
= −24
mA
I
OH
= −24
mA (Note 5)
I
OUT
=
50
µA
V
IN
=
V
IL
or V
IH
V
µA
mA
mA
mA
µA
I
OL
=
24 mA
I
OL
=
24 mA (Note 5)
V
I
=
V
CC
, GND
V
I
=
V
CC
−
2.1V
V
OLD
=
1.65V Max
V
OHD
=
3.85V Min
V
IN
=
V
CC
or GND
V
I
(OE)
=
V
IL
, V
IH
V
I
=
V
CC
, GND
V
O
=
V
CC
, GND
Note 5:
All outputs loaded; thresholds on input associated with output under test.
Note 6:
Maximum test duration 2.0 ms, one output loaded at a time.
AC Electrical Characteristics for AC
V
CC
Symbol
Parameter
(V)
(Note 7)
t
PLH
t
PHL
t
PZH
t
PZL
t
PHZ
t
PLZ
Propagation Delay
A
n
to B
n
or B
n
to A
n
Propagation Delay
A
n
to B
n
or B
n
to A
n
Output Enable Time
Output Enable Time
Output Disable Time
Output Disable Time
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
Note 7:
Voltage Range 3.3 is 3.3V
±
0.3V
Voltage Range 5.0 is 5.0V
±
0.5V
T
A
= +25°C
C
L
=
50 pF
Min
1.5
1.5
1.5
1.5
2.5
1.5
2.5
1.5
2.0
1.5
2.0
1.5
Typ
5.0
3.5
5.0
3.5
7.0
5.0
7.5
5.5
6.5
5.5
7.0
5.5
Max
8.5
6.5
8.5
6.0
11.5
8.5
12.0
9.0
12.0
9.0
11.5
9.0
T
A
= −40°C
to
+85°C
C
L
=
50 pF
Min
1.0
1.0
1.0
1.0
2.0
1.0
2.0
1.0
1.0
1.0
1.5
1.0
Max
9.0
7.0
9.0
7.0
12.5
9.0
13.5
9.5
12.5
10.0
13.0
10.0
ns
ns
ns
ns
ns
ns
Units
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4
Embedded System
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