74AHC240; 74AHCT240
Octal buffer/line driver; inverting; 3-state
Rev. 4 — 25 September 2013
Product data sheet
1. General description
The 74AHC240 and 74AHCT240 are 8-bit inverting buffer/line drivers with 3-state outputs.
These devices can be used as two 4-bit buffers or one 8-bit buffer. They feature two
output enables (1OE and 2OE), each controlling four of the 3-state outputs. A HIGH on
nOE causes the outputs to assume a high-impedance OFF-state. Inputs are over voltage
tolerant. This feature allows the use of these devices as translators in mixed voltage
environments.
2. Features and benefits
Balanced propagation delays
All inputs have a Schmitt-trigger action
Inputs accepts voltages higher than V
CC
For 74AHC240 only: operates with CMOS input levels
For 74AHCT240 only: operates with TTL input levels
ESD protection:
HBM JESD22-A114F exceeds 2000 V
CDM JESD22-C101D exceeds 1000 V
Multiple package options
Specified from
40 C
to +85
C
and from
40 C
to +125
C
3. Ordering information
Table 1.
Ordering information
Package
Temperature range
74AHC240D
74AHCT240D
74AHC240PW
74AHCT240PW
74AHC240BQ
74AHCT240BQ
40 C
to +125
C
DHVQFN20
40 C
to +125
C
TSSOP20
40 C
to +125
C
Name
SO20
Description
plastic small outline package; 20 leads;
body width 7.5 mm
plastic thin shrink small outline package; 20 leads;
body width 4.4 mm
Version
SOT163-1
SOT360-1
Type number
plastic dual in-line compatible thermal enhanced
SOT764-1
very thin quad flat package; no leads; 20 terminals;
body 2.5
4.5
0.85 mm
NXP Semiconductors
74AHC240; 74AHCT240
Octal buffer/line driver; inverting; 3-state
4. Functional diagram
1
EN
18
16
14
12
2
2
17
4
15
6
13
8
11
1
19
1A0
2A0
1A1
2A1
1A2
2A2
1A3
2A3
1OE
2OE
mgu779
1Y0 18
2Y0 3
1Y1 16
2Y1 5
4
6
8
19
1Y2 14
2Y2
7
11
13
15
17
EN
9
7
5
3
mgu778
1Y3 12
2Y3 9
Fig 1.
Logic symbol
Fig 2.
IEC logic symbol
5. Pinning information
5.1 Pinning
74AHC240
74AHCT240
1OE
2
3
4
5
6
7
8
9
GND 10
2A3 11
GND
(1)
1
terminal 1
index area
20 V
CC
19 2OE
18 1Y0
17 2A0
16 1Y1
15 2A1
14 1Y2
13 2A2
12 1Y3
74AHC240
74AHCT240
1OE
1A0
2Y0
1A1
2Y1
1A2
2Y2
1A3
2Y3
1
2
3
4
5
6
7
8
9
20 V
CC
19 2OE
18 1Y0
17 2A0
16 1Y1
15 2A1
14 1Y2
13 2A2
12 1Y3
11 2A3
001aal192
1A0
2Y0
1A1
2Y1
1A2
2Y2
1A3
2Y3
GND 10
001aal193
Transparent top view
(1) This is not a supply pin. The substrate is attached to this
pad using conductive die attach material. There is no
electrical or mechanical requirement to solder this pad.
However, if it is soldered, the solder land should remain
floating or be connected to GND.
Fig 3.
74AHC_AHCT240
Pin configuration SO20 and TSSOP20
Fig 4.
Pin configuration DHVQFN20
© NXP B.V. 2013. All rights reserved.
All information provided in this document is subject to legal disclaimers.
Product data sheet
Rev. 4 — 25 September 2013
2 of 16
NXP Semiconductors
74AHC240; 74AHCT240
Octal buffer/line driver; inverting; 3-state
5.2 Pin description
Table 2.
Symbol
1OE
2OE
Pin description
Pin
1
19
Description
output enable input (active LOW)
output enable input (active LOW)
data input
data input
data output
data output
ground (0 V)
power supply
1A0, 1A1, 1A2, 1A3 2, 4, 6, 8
2A0, 2A1, 2A2, 2A3 17, 15, 13, 11
1Y0, 1Y1, 1Y2, 1Y3 18, 16, 14, 12
2Y0, 2Y1, 2Y2, 2Y3 3, 5, 7, 9
GND
V
CC
10
20
6. Functional description
Table 3.
Control
nOE
L
L
H
[1]
Function table
[1]
Input
nAn
L
H
X
Output
nYn
H
L
Z
H = HIGH voltage level; L = LOW voltage level; X = don’t care; Z = high-impedance OFF-state.
7. Limiting values
Table 4.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).
Symbol
V
CC
V
I
I
IK
I
OK
I
O
I
CC
I
GND
T
stg
P
tot
[1]
[2]
Parameter
supply voltage
input voltage
input clamping current
output clamping current
output current
supply current
ground current
storage temperature
total power dissipation
Conditions
Min
0.5
0.5
Max
+7.0
+7.0
-
20
25
75
-
+150
500
Unit
V
V
mA
mA
mA
mA
mA
C
mW
V
I
<
0.5
V
V
O
<
0.5
V or V
O
> V
CC
+ 0.5 V
V
O
=
0.5
V to (V
CC
+ 0.5 V)
[1]
[1]
20
-
-
-
75
65
T
amb
=
40 C
to +125
C
[2]
-
The minimum input and output voltage ratings may be exceeded if the input and output current ratings are observed.
For SO20 package: above 70
C
the value of P
tot
derates linearly with 8.0 mW/K.
For TSSOP20 package: above 60
C
the value of P
tot
derates linearly with 5.5 mW/K.
For DHVQFN20 package: above 60
C
the value of P
tot
derates linearly with 4.5 mW/K.
74AHC_AHCT240
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2013. All rights reserved.
Product data sheet
Rev. 4 — 25 September 2013
3 of 16
NXP Semiconductors
74AHC240; 74AHCT240
Octal buffer/line driver; inverting; 3-state
8. Recommended operating conditions
Table 5.
Symbol
74AHC240
V
CC
V
I
V
O
T
amb
t/V
74AHCT240
V
CC
V
I
V
O
T
amb
t/V
supply voltage
input voltage
output voltage
ambient temperature
input transition rise and fall rate
V
CC
= 5 V
0.5 V
4.5
0
0
40
-
5.0
-
-
+25
-
5.5
5.5
V
CC
+125
20
V
V
V
C
ns/V
supply voltage
input voltage
output voltage
ambient temperature
input transition rise and fall rate
V
CC
= 3.3 V
0.3 V
V
CC
= 5 V
0.5 V
2.0
0
0
40
-
-
5.0
-
-
+25
-
-
5.5
5.5
V
CC
+125
100
20
V
V
V
C
ns/V
ns/V
Recommended operating conditions
Parameter
Conditions
Min
Typ
Max
Unit
9. Static characteristics
Table 6.
Static characteristics
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
74AHC240
V
IH
HIGH-level
input voltage
V
CC
= 2.0 V
V
CC
= 3.0 V
V
CC
= 5.5 V
V
IL
LOW-level
input voltage
V
CC
= 2.0 V
V
CC
= 3.0 V
V
CC
= 5.5 V
V
OH
HIGH-level
V
I
= V
IH
or V
IL
output voltage
I
O
=
50 A;
V
CC
= 2.0 V
I
O
=
50 A;
V
CC
= 3.0 V
I
O
=
50 A;
V
CC
= 4.5 V
I
O
=
4.0
mA; V
CC
= 3.0 V
I
O
=
8.0
mA; V
CC
= 4.5 V
V
OL
LOW-level
V
I
= V
IH
or V
IL
output voltage
I
O
= 50
A;
V
CC
= 2.0 V
I
O
= 50
A;
V
CC
= 3.0 V
I
O
= 50
A;
V
CC
= 4.5 V
I
O
= 4.0 mA; V
CC
= 3.0 V
I
O
= 8.0 mA; V
CC
= 4.5 V
74AHC_AHCT240
Conditions
Min
1.5
2.1
3.85
-
-
-
1.9
2.9
4.4
2.58
3.94
-
-
-
-
-
25
C
Typ
-
-
-
-
-
-
2.0
3.0
4.5
-
-
0
0
0
-
-
Max
-
-
-
0.5
0.9
1.65
-
-
-
-
-
0.1
0.1
0.1
0.36
0.36
40 C
to +85
C 40 C
to +125
C
Unit
Min
1.5
2.1
3.85
-
-
-
1.9
2.9
4.4
2.48
3.80
-
-
-
-
-
Max
-
-
-
0.5
0.9
1.65
-
-
-
-
-
0.1
0.1
0.1
0.44
0.44
Min
1.5
2.1
3.85
-
-
-
1.9
2.9
4.4
2.40
3.70
-
-
-
-
-
Max
-
-
-
0.5
0.9
1.65
-
-
-
-
-
0.1
0.1
0.1
0.55
0.55
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2013. All rights reserved.
Product data sheet
Rev. 4 — 25 September 2013
4 of 16
NXP Semiconductors
74AHC240; 74AHCT240
Octal buffer/line driver; inverting; 3-state
Table 6.
Static characteristics
…continued
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
I
I
I
OZ
input leakage
current
Conditions
Min
V
I
= 5.5 V or GND;
V
CC
= 0 V to 5.5 V
-
-
25
C
Typ
-
-
Max
0.1
0.25
40 C
to +85
C 40 C
to +125
C
Unit
Min
-
-
Max
1.0
2.5
Min
-
-
Max
2.0
10.0
A
A
OFF-state
V
I
= V
IH
or V
IL
;
output current V
O
= V
CC
or GND;
V
CC
= 5.5 V
supply current V
I
= V
CC
or GND; I
O
= 0 A;
V
CC
= 5.5 V
input
capacitance
output
capacitance
HIGH-level
input voltage
LOW-level
input voltage
V
CC
= 4.5 V to 5.5 V
V
CC
= 4.5 V to 5.5 V
V
I
= V
CC
or GND
I
CC
C
I
C
O
-
-
-
-
3
4
4.0
10
-
-
-
-
40
10
-
-
-
-
80
10
-
A
pF
pF
74AHCT240
V
IH
V
IL
V
OH
2.0
-
-
-
-
0.8
2.0
-
-
0.8
2.0
-
-
0.8
V
V
HIGH-level
V
I
= V
IH
or V
IL
; V
CC
= 4.5 V
output voltage
I
O
=
50 A
I
O
=
8.0
mA
LOW-level
V
I
= V
IH
or V
IL
; V
CC
= 4.5 V
output voltage
I
O
= 50
A
I
O
= 8.0 mA
input leakage
current
V
I
= 5.5 V or GND;
V
CC
= 0 V to 5.5 V
4.4
3.94
-
-
-
-
4.5
-
0
-
-
-
-
-
0.1
0.36
0.1
0.25
4.4
3.80
-
-
-
-
-
-
0.1
0.44
1.0
2.5
4.4
3.70
-
-
-
-
-
-
0.1
0.55
2.0
10.0
V
V
V
V
A
A
V
OL
I
I
I
OZ
OFF-state
V
I
= V
IH
or V
IL
;
output current V
O
= V
CC
or GND per input
pin; other inputs at
V
CC
or GND; I
O
= 0 A;
V
CC
= 5.5 V
supply current V
I
= V
CC
or GND; I
O
= 0 A;
V
CC
= 5.5 V
additional
per input pin;
supply current V
I
= V
CC
2.1 V;
other pins at V
CC
or GND;
I
O
= 0 A; V
CC
= 4.5 V to 5.5 V
input
capacitance
output
capacitance
V
I
= V
CC
or GND
I
CC
I
CC
-
-
-
-
4.0
1.35
-
-
40
1.5
-
-
80
1.5
A
mA
C
I
C
O
-
-
3
4
10
-
-
-
10
-
-
-
10
-
pF
pF
74AHC_AHCT240
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2013. All rights reserved.
Product data sheet
Rev. 4 — 25 September 2013
5 of 16
51单片机
