Datasheet

UNISONIC TECHNOLOGIES CO., LTD
U74HCT245
CMOS IC
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
SOP-20

DESCRIPTION
The U74HCT245 is designed for the asynchronous
communication
between
data
buses.
While
the
direction-control(DIR) is high, data transmits from the A bus to the
B bus. Data transmits from the B bus to the A bus if DIR is low.
SSOP-20
The output-enable OE will isolate the device from the buses
when high voltage is applied on it.
TSSOP-20

FEATURES
* Operate from 4.5V to 5.5V
* Typical tPD is 14ns at 5.5V
* Inputs are TTL Voltage Compatible

ORDERING INFORMATION
Ordering Number
U74HCT245G-P20-R
U74HCT245G-R20-R
U74HCT245G-S20-R

Package
TSSOP-20
SSOP-20
SOP-20
Packing
Tape Reel
Tape Reel
Tape Reel
MARKING
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Copyright © 2015 Unisonic Technologies Co., Ltd
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U74HCT245
CMOS IC

PIN CONFIGURATION

FUNCTION TABLE
INPUT
OE
DIR
FUNCTION
X
H
Isolation
L
H
Transmit data from A bus to B bus
L
L
Transmit data from B bus to A bus
Note: H: HIGH voltage level; L: LOW voltage level.

LOGIC DIAGRAM
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U74HCT245

CMOS IC
ABSOLUTE MAXIMUM RATING
PARAMETER
SYMBOL
RATINGS
UNIT
Supply Voltage
VCC
-0.5~7.0
V
Input Clamp Current (ViN<0)
IIK
±20
mA
Output Clamp Current (VOUT<0)
IOK
±20
mA
Output Current
IOUT
±35
mA
VCC or GND Current
ICC
±70
mA
Storage Temperature
TSTG
-65 ~ +150
°C
Notes: 1. Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
2. The input and output voltage ratings may be exceeded if the input and output current ratings are
observed.

RECOMMENDED OPERATING CONDITIONS
PARAMETER
Supply Voltage
Input Voltage
Output Voltage
Input Transition Rise or Fall Rate
Operating Temperature

SYMBOL
VCC
VIN
VOUT
tT
TOPR
MIN
4.5
0
0
TYP
5
-40
MAX
5.5
VCC
VCC
500
85
UNIT
V
V
V
ns
°C
ELECTRICAL CHARACTERISTICS (TA=25°С, unless otherwise specified)
PARAMETER
High-Level input voltage
Low-Level output voltage
SYMBOL
TEST CONDITIONS
VIH
VCC=4.5V~5.5V
VIL
VCC=4.5V~5.5V
VCC=4.5V, IOH=-20μA
High-Level Output Voltage
VOH
VCC=4.5V, IOH=-6mA
VCC=4.5V, IOL=20μA
Low-Level Output Voltage
VOL
VCC=4.5V, IOH=6mA
Input Current of DIR or OE
II(LEAK) VCC=5.5V, VIN=VCC or GND
Output OFF -state current
IOZ
VCC=5.5V, VOUT=VCC or GND
Quiescent Supply Current
ICC
VCC=5.5V, VIN=VCC or GND, IOUT=0
VCC=5.5V,One input at 0.5V or
∆ICC
Additional Quiescent Supply Current
2.4V,other inputs at 0 or VCC
Input Capacitance of DIR or OE
VCC=5.5V, VIN=VCC or GND
CIN
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MIN
2.0
4.4
3.98
TYP
1.6
1.2
4.499
4.3
0.001
0.17
±0.1
±0.01
MAX
0.1
0.26
±100
±0.5
8
UNIT
V
V
V
V
V
V
nA
μA
μA
1.4
2.4
mA
3
10
pF
0.8
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CMOS IC
SWITCHING CHARACTERISTICS (TA=25°С, RL=1kΩ,unless otherwise specified)
CL=50pF
PARAMETER
Propagation delay from input
(A or B) to output (B or A)
SYMBOL
TEST CONDITIONS
tPD
VCC=4.5V
(tPLH/tPHL) VCC=5.5V
3-state output enable time from input
VCC=4.5V
tEN
( OE ) to output (A or B)
(tPZL/tPZH) VCC=5.5V
3-state output disable time from
VCC=4.5V
tDIS
input ( OE ) to output (A or B)
(tPLZ/tPHZ) VCC=5.5V
tT
VCC=4.5V
Output transition time, (A or B)
(tR/tF) VCC=5.5V
CL=150pF
PARAMETER
SYMBOL
TEST CONDITIONS
Propagation delay from input
tPD
VCC=4.5V
(A or B) to output (B or A)
(tPLH/tPHL) VCC=5.5V
3-state output enable time from input
VCC=4.5V
tEN
( OE ) to output (A or B)
(tPZL/tPZH) VCC=5.5V
tT
VCC=4.5V
Output transition time, (A or B)
(tR/tF) VCC=5.5V

MIN
TYP
16
14
25
22
26
23
9
8
MAX
22
20
46
41
40
36
12
11
UNIT
ns
ns
ns
ns
ns
ns
ns
ns
MIN
TYP
20
18
36
30
17
14
MAX
30
27
59
53
42
38
UNIT
ns
ns
ns
ns
ns
ns
OPERATING CHARACTERISTICS
PARAMETER
Power Dissipation Capacitance
SYMBOL
TEST CONDITIONS
CPD
No load
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RATINGS
40
UNIT
pF
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CMOS IC
TEST CIRCUIT AND WAVEFORMS
Note: CL includes probe and jig capacitance.
PRR ≤1MHz, ZO = 50Ω, tR ≤6ns, tF ≤6ns
3V
OE
1.3V
1.3V
0V
3V
A/B
1.3V
1.3V
VCC
B/A
0V
B/A
VOH
1.3V
1.3V
B/A
1.3V
10%
1.3V
VOL
Propagation Delay Times
VOL
90%
VOH
0V
Enable and Disable Times
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
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