TECHNICAL DATA
IN74HCT245A
Octal 3-State Noninverting
Bus Transceiver
High-Performance Silicon-Gate CMOS
The IN74HCT245A is identical in pinout to the LS/ALS245.This
device may be used as a level converter for interfacing TTL or NMOS
outputs to High Speed CMOS inputs.
The IN74HCT245A is a 3-state noninverting transceiver that is used
for 2-way asynchronous communication between data buses. The device
has an active-low Output Enable pin, which is used to place the I/O ports
into high-impedance states. The Direction control determines whether
data flows from A to B or from B to A.
•
TTL/NMOS Compatible Input Levels
•
Outputs Directly Interface to CMOS, NMOS, and TTL
•
Operating Voltage Range: 4.5 to 5.5 V
•
Low Input Current: 1.0
μA
ORDERING INFORMATION
IN74HCT245AN Plastic
IN74HCT245ADW SOIC
IN74HCT245ATDS SOIC
T
A
= -55° to 125° C for all packages
PIN ASSIGNMENT
LOGIC DIAGRAM
FUNCTION TABLE
PIN 20=V
CC
PIN 10 = GND
Control Inputs
Output
Enable
L
Direction
L
Operation
Data Transmitted
from Bus B to
Bus A
Data Transmitted
from Bus A to
Bus B
Buses Isolated
(High Impedance
State)
L
H
H
X
X = don’t care
Rev. 00
IN74HCT245A
MAXIMUM RATINGS
*
Symbol
V
CC
V
IN
V
OUT
I
IN
I
OUT
I
CC
P
D
Tstg
T
L
*
Parameter
DC Supply Voltage (Referenced to GND)
DC Input Voltage (Referenced to GND)
DC Output Voltage (Referenced to GND)
DC Input Current, per Pin
DC Output Current, per Pin
DC Supply Current, V
CC
and GND Pins
Power Dissipation in Still Air, Plastic DIP+
SOIC Package+
Storage Temperature
Lead Temperature, 1 mm from Case for 10 Seconds
(Plastic DIP or SOIC Package)
Value
-0.5 to +7.0
-1.5 to V
CC
+1.5
-0.5 to V
CC
+0.5
±20
±35
±75
750
500
-65 to +150
260
Unit
V
V
V
mA
mA
mA
mW
°C
°C
Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the Recommended Operating Conditions.
+Derating - Plastic DIP: - 10 mW/°C from 65° to 125°C
SOIC Package: : - 7 mW/°C from 65° to 125°C
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
IN
, V
OUT
T
A
t
r
, t
f
Parameter
DC Supply Voltage (Referenced to GND)
DC Input Voltage, Output Voltage (Referenced to GND)
Operating Temperature, All Package Types
Input Rise and Fall Time (Figure 1)
Min
4.5
0
-55
0
Max
5.5
V
CC
+125
500
Unit
V
V
°C
ns
This device contains protection circuitry to guard against damage due to high static voltages or electric fields.
However, precautions must be taken to avoid applications of any voltage higher than maximum rated voltages to this
high-impedance circuit. For proper operation, V
IN
and V
OUT
should be constrained to the range GND≤(V
IN
or
V
OUT
)≤V
CC
.
Unused inputs must always be tied to an appropriate logic voltage level (e.g., either GND or V
CC
). Unused
outputs must be left open.
Rev. 00
IN74HCT245A
DC ELECTRICAL CHARACTERISTICS
(Voltages Referenced to GND)
V
CC
Symbol
Parameter
Test Conditions
V
Guaranteed Limit
25
°C
to
-55°C
2.0
2.0
0.8
0.8
4.4
5.4
3.98
0.1
0.1
0.26
±0.1
±0.5
≤85
°C
2.0
2.0
0.8
0.8
4.4
5.4
3.84
0.1
0.1
0.33
±1.0
±5.0
≤125
°C
2.0
2.0
0.8
0.8
4.4
5.4
3.7
0.1
0.1
0.4
±1.0
±10
μA
μA
V
Unit
V
IH
V
IL
V
OH
Minimum High-
Level Input Voltage
Maximum Low -
Level Input Voltage
Minimum High-
Level Output Voltage
V
OUT
=0.1 V or V
CC
-0.1 V
⎢I
OUT
⎢≤
20
μA
V
OUT
=0.1 V or V
CC
-0.1 V
⎢I
OUT
⎢ ≤
20
μA
V
IN
=V
IH
or V
IL
⎢I
OUT
⎢ ≤
20
μA
V
IN
=V
IH
or V
IL
⎢I
OUT
⎢ ≤
6.0 mA
4.5
5.5
4.5
5.5
4.5
5.5
4.5
4.5
5.5
4.5
5.5
5.5
V
V
V
V
OL
Maximum Low-
Level Output Voltage
V
IN
= V
IL
or V
IH
⎢I
OUT
⎢ ≤
20
μA
V
IN
= V
IL
or V
IH
⎢I
OUT
⎢ ≤
6.0 mA
I
IN
I
OZ
Maximum Input
Leakage Current
Maximum Three-
State Leakage
Current
V
IN
=V
CC
or GND,
Pin 1 or 19
Output in High-Impedance
State
V
IN
= V
IL
or V
IH
V
OUT
=V
CC
or GND,
I/O Pins
V
IN
=V
CC
or GND
I
OUT
=0μA
V
IN
=2.4 V, Any One Input
V
IN
=V
CC
or GND, Other
Inputs
I
OUT
=0μA
I
CC
Maximum Quiescent
Supply Current
(per Package)
Additional Quiescent
Supply Current
5.5
4.0
40
160
μA
ΔI
CC
≥-55°C
25°C to
125°C
2.4
mA
5.5
2.9
Rev. 00
IN74HCT245A
AC ELECTRICAL CHARACTERISTICS
(V
CC
=5.0 V
±
10%, C
L
=50pF,Input t
r
=t
f
=6.0 ns)
Guaranteed Limit
Symbol
Parameter
25
°C
to
-55°C
22
32
30
12
10
15
≤85°C
≤125°C
Unit
t
PLH
, t
PHL
t
PLZ
, t
PHZ
t
PZL
, t
PZH
t
TLH
, t
THL
C
IN
C
OUT
Maximum Propagation Delay, A to B or B to A
(Figures 1 and 3)
Maximum Propagation Delay , Direction or
Output Enable to A or B (Figures 2 and 4)
Maximum Propagation Delay , Direction or
Output Enable to A or B (Figures 2 and 4)
Maximum Output Transition Time, Any Output
(Figures 1 and 3)
Maximum Input Capacitance (Pin 1 or Pin 19)
Maximum Three-State I/O Capacitance
(I/O in High-Impedance State)
Power Dissipation Capacitance (Per Enable
Output)
28
40
38
15
10
15
33
48
45
18
10
15
ns
ns
ns
ns
pF
pF
Typical @25°C,V
CC
=5.0 V
97
pF
C
PD
Used to determine the no-load dynamic power
consumption:
P
D
=C
PD
V
CC2
f+I
CC
V
CC
Figure 1. Switching Waveforms
Figure 2. Switching Waveforms
Rev. 00
IN74HCT245A
Figure 3. Test Circuit
Figure 4. Test Circuit
EXPANDED LOGIC DIAGRAM
Rev. 00
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