74HC240D,74HC244D
CMOS Digital Integrated Circuits Silicon Monolithic
74HC240D,74HC244D
1. Functional Description
• Octal Bus Buffer
74HC240D: INVERTED, 3-STATE OUTPUTS
74HC244D: NON-INVERTED, 3-STATE OUTPUTS
2. General
The 74HC240D and 74HC244D are high speed CMOS OCTAL BUS BUFFERs fabricated with silicon gate C
2
MOS
technology.
They achieve the high speed operation similar to equivalent LSTTL while maintaining the CMOS low power
dissipation.
The 74HC240D is an inverting 3-state buffer and the 74HC244D are non-inverting 3-state buffers having two
active-low output enables.
These devices are designed to be used with 3-state memory address drivers, etc.
All inputs are equipped with protection circuits against static discharge or transient excess voltage.
3. Features
(1)
(2)
(3)
(4)
High speed: t
pd
= 10 ns (typ.) at V
CC
= 6.0 V
Low power dissipation: I
CC
= 4.0
µA
(max) at T
a
= 25
Balanced propagation delays: t
PLH
≈
t
PHL
Wide operating voltage range: V
CC(opr)
= 2.0 V to 6.0 V
4. Packaging
SOIC20
Start of commercial production
©2016 Toshiba Corporation
1
2016-04
2016-05-24
Rev.2.0
74HC240D,74HC244D
5. Pin Assignment
74HC240D
74HC244D
6. Marking
74HC240D
74HC244D
7. IEC Logic Symbol
74HC240D
74HC244D
©2016 Toshiba Corporation
2
2016-05-24
Rev.2.0
74HC240D,74HC244D
8. Truth Table
Input G
L
L
H
Input An
L
H
X
Output Yn
L
H
Z
Output Yn
H
L
Z
X:
Z:
Yn:
Yn:
Don't care
High impedance
74HC244D
74HC240D
9. Absolute Maximum Ratings (Note)
Characteristics
Supply voltage
Input voltage
Output voltage
Input diode current
Output diode current
Output current
V
CC
/ground current
Power dissipation
Storage temperature
Symbol
V
CC
V
IN
V
OUT
I
IK
I
OK
I
OUT
I
CC
P
D
T
stg
Rating
-0.5 to 7.0
-0.5 to V
CC
+ 0.5
-0.5 to V
CC
+ 0.5
±20
±20
±35
±75
500
-65 to 150
Unit
V
V
V
mA
mA
mA
mA
mW
Note:
Exceeding any of the absolute maximum ratings, even briefly, lead to deterioration in IC performance or even
destruction.
Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the
significant change in temperature, etc.) may cause this product to decrease in the reliability significantly even
if the operating conditions (i.e. operating temperature/current/voltage, etc.) are within the absolute maximum
ratings and the operating ranges.
Please design the appropriate reliability upon reviewing the Toshiba Semiconductor Reliability Handbook
(“Handling Precautions”/“Derating Concept and Methods”) and individual reliability data (i.e. reliability test report
and estimated failure rate, etc).
10. Operating Ranges (Note)
Characteristics
Supply voltage
Input voltage
Output voltage
Operating temperature
Input rise and fall times
Symbol
V
CC
V
IN
V
OUT
T
opr
t
r
,t
f
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
Test Condition
Rating
2.0 to 6.0
0 to V
CC
0 to V
CC
-40 to 85
0 to 1000
0 to 500
0 to 400
Unit
V
V
V
ns
Note:
The operating ranges must be maintained to ensure the normal operation of the device.
Unused inputs must be tied to either V
CC
or GND.
©2016 Toshiba Corporation
3
2016-05-24
Rev.2.0
74HC240D,74HC244D
11. Electrical Characteristics
11.1. DC Characteristics (Unless otherwise specified, T
a
= 25
)
Characteristics
High-level input voltage
Symbol
V
IH
Test Condition
V
CC
(V)
2.0
4.5
6.0
Low-level input voltage
V
IL
2.0
4.5
6.0
High-level output voltage
V
OH
V
IN
= V
IH
or V
IL
I
OH
= -20
µA
2.0
4.5
6.0
I
OH
= -6 mA
I
OH
= -7.8 mA
Low-level output voltage
V
OL
V
IN
= V
IH
or V
IL
I
OL
= 20
µA
4.5
6.0
2.0
4.5
6.0
I
OL
= 6 mA
I
OL
= 7.8 mA
3-state output OFF-state
leakage current
Input leakage current
Quiescent supply current
I
OZ
I
IN
I
CC
V
IN
= V
IH
or V
IL
V
OUT
= V
CC
or GND
V
IN
= V
CC
or GND
V
IN
= V
CC
or GND
4.5
6.0
6.0
6.0
6.0
Min
1.50
3.15
4.20
1.9
4.4
5.9
4.18
5.68
Typ.
2.0
4.5
6.0
4.31
5.80
0.0
0.0
0.0
0.17
0.18
Max
0.50
1.35
1.80
0.1
0.1
0.1
0.26
0.26
±0.5
±0.1
4.0
µA
µA
µA
V
V
V
Unit
V
11.2. DC Characteristics (Unless otherwise specified, T
a
= -40 to 85
)
Characteristics
High-level input voltage
Symbol
V
IH
Test Condition
V
CC
(V)
2.0
4.5
6.0
Low-level input voltage
V
IL
2.0
4.5
6.0
High-level output voltage
V
OH
V
IN
= V
IH
or V
IL
I
OH
= -20
µA
2.0
4.5
6.0
I
OH
= -6 mA
I
OH
= -7.8 mA
Low-level output voltage
V
OL
V
IN
= V
IH
or V
IL
I
OL
= 20
µA
4.5
6.0
2.0
4.5
6.0
I
OL
= 6 mA
I
OL
= 7.8 mA
3-state output OFF-state
leakage current
Input leakage current
Quiescent supply current
I
OZ
I
IN
I
CC
V
IN
= V
IH
or V
IL
V
OUT
= V
CC
or GND
V
IN
= V
CC
or GND
V
IN
= V
CC
or GND
4.5
6.0
6.0
6.0
6.0
Min
1.50
3.15
4.20
1.9
4.4
5.9
4.13
5.63
Max
0.50
1.35
1.80
0.1
0.1
0.1
0.33
0.33
±5.0
±1.0
40.0
µA
µA
µA
V
V
V
Unit
V
©2016 Toshiba Corporation
4
2016-05-24
Rev.2.0
74HC240D,74HC244D
11.3. AC Characteristics (Unless otherwise specified, T
a
= 25
, Input: t
r
= t
f
= 6 ns)
Characteristics
Output transition time
Part Number
Symbol
t
TLH
,t
THL
Note
Test
Condition
C
L
(pF)
50
V
CC
(V)
2.0
4.5
6.0
Propagation delay time
t
PLH
,t
PHL
50
2.0
4.5
6.0
150
2.0
4.5
6.0
Output enable time
t
PZL
,t
PZH
R
L
= 1 kΩ
50
2.0
4.5
6.0
150
2.0
4.5
6.0
Output disable time
t
PLZ
,t
PHZ
R
L
= 1 kΩ
50
2.0
4.5
6.0
Input capacitance
Output capacitance
Power dissipation
capacitance
74HC240D
74HC244D
C
IN
C
OUT
C
PD
(Note 1)
Min
Typ.
25
7
6
36
12
10
51
17
14
48
16
14
63
21
18
32
15
14
5
10
31
33
Max
60
12
10
90
18
15
130
26
22
125
25
21
165
33
28
125
25
21
10
pF
pF
pF
ns
ns
ns
Unit
ns
Note 1: C
PD
is defined as the value of the internal equivalent capacitance which is calculated from the operating current
consumption without load. Average operating current can be obtained by the equation.
I
CC(opr)
= C
PD
×
V
CC
×
f
IN
+ I
CC
/8 (per bit)
11.4. AC Characteristics
(Unless otherwise specified, T
a
= -40 to 85
, Input: t
r
= t
f
= 6 ns)
Characteristics
Output transition time
Symbol
t
TLH
,t
THL
Test Condition
C
L
(pF)
50
V
CC
(V)
2.0
4.5
6.0
Propagation delay time
t
PLH
,t
PHL
50
2.0
4.5
6.0
150
2.0
4.5
6.0
Output enable time
t
PZL
,t
PZH
R
L
= 1 kΩ
50
2.0
4.5
6.0
150
2.0
4.5
6.0
Output disable time
t
PLZ
,t
PHZ
R
L
= 1 kΩ
50
2.0
4.5
6.0
Input capacitance
C
IN
Min
Max
75
15
13
115
23
20
165
33
28
155
31
26
205
41
35
155
31
26
10
pF
ns
ns
ns
Unit
ns
©2016 Toshiba Corporation
5
2016-05-24
Rev.2.0
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