M74HC240
OCTAL BUS BUFFER
WITH 3 STATE OUTPUTS (INVERTED)
s
s
s
s
s
s
s
HIGH SPEED:
t
PD
= 10ns (TYP.) at V
CC
= 6V
LOW POWER DISSIPATION:
I
CC
= 4µA(MAX.) at T
A
=25°C
HIGH NOISE IMMUNITY:
V
NIH
= V
NIL
= 28 % V
CC
(MIN.)
SYMMETRICAL OUTPUT IMPEDANCE:
|I
OH
| = I
OL
= 6mA (MIN)
BALANCED PROPAGATION DELAYS:
t
PLH
≅
t
PHL
WIDE OPERATING VOLTAGE RANGE:
V
CC
(OPR) = 2V to 6V
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 240
DIP
SOP
ORDER CODES
PACKAGE
DIP
SOP
TSSOP
TUBE
DESCRIPTION
The M74HC240 is an advanced high-speed
CMOS OCTAL BUS BUFFER (3-STATE)
fabricated with silicon gate C
2
MOS technology.
G control input governs four BUS BUFFERs.
bs
O
PIN CONNECTION AND IEC LOGIC SYMBOLS
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-
This device is designed to be used with 3 state
memory address drivers, etc.
All inputs are equipped with protection circuits
against static discharge and transient excess
voltage.
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M74HC240B1R
M74HC240M1R
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TSSOP
T&R
M74HC240RM13TR
M74HC240TTR
July 2001
1/10
M74HC240
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No
1
2, 4, 6, 8
9, 7, 5, 3
11, 13, 15,
17
18, 16, 14,
12
19
10
20
SYMBOL
1G
1A1 to 1A4
2Y1 to 2Y4
2A1 to 2A4
1Y1 to 1Y4
2G
GND
V
CC
NAME AND FUNCTION
Output Enable Input
Data Inputs
Data Outputs
Data Inputs
Data Outputs
Output Enable Input
Ground (0V)
Positive Supply Voltage
TRUTH TABLE
INPUTS
G
L
L
H
X : Don’t Care
Z : High Impedance
An
L
H
X
ABSOLUTE MAXIMUM RATINGS
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
Supply Voltage
DC Input Voltage
DC Output Voltage
Parameter
DC Input Diode Current
DC Output Current
Power Dissipation
Storage Temperature
DC Output Diode Current
I
CC
or I
GND
DC V
CC
or Ground Current
P
D
T
L
b
O
et
l
so
T
stg
od
r
P
e
uc
s)
t(
O
-
so
b
te
le
ro
P
OUTPUT
Yn
H
L
Z
uc
d
s)
t(
Value
-0.5 to +7
-0.5 to V
CC
+ 0.5
-0.5 to V
CC
+ 0.5
±
20
±
20
±
35
±
70
500(*)
-65 to +150
300
Unit
V
V
V
mA
mA
mA
mA
mW
°C
°C
Lead Temperature (10 sec)
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied
(*) 500mW at 65
°
C; derate to 300mW by 10mW/
°
C from 65
°
C to 85
°
C
RECOMMENDED OPERATING CONDITIONS
Symbol
V
CC
V
I
V
O
T
op
t
r
, t
f
Supply Voltage
Input Voltage
Output Voltage
Operating Temperature
Input Rise and Fall Time
V
CC
= 2.0V
V
CC
= 4.5V
V
CC
= 6.0V
2/10
Parameter
Value
2 to 6
0 to V
CC
0 to V
CC
-55 to 125
0 to 1000
0 to 500
0 to 400
Unit
V
V
V
°C
ns
ns
ns
M74HC240
AC ELECTRICAL CHARACTERISTICS
(C
L
= 50 pF, Input t
r
= t
f
= 6ns)
Test Condition
Symbol
Parameter
V
CC
(V)
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
C
L
(pF)
T
A
= 25°C
Min.
Typ.
25
7
6
36
12
10
51
17
14
48
16
14
63
21
18
32
15
14
Max.
60
12
10
90
18
15
130
26
22
125
25
21
165
33
28
125
25
21
Value
-40 to 85°C
Min.
Max.
75
19
13
115
23
20
165
33
28
155
31
25
205
41
35
155
31
26
-55 to 125°C
Min.
Max.
90
18
15
135
27
23
195
39
33
190
38
32
250
50
43
190
38
32
ns
Unit
t
TLH
t
THL
Output Transition
Time
t
PLH
t
PHL
Propagation Delay
Time
50
50
ns
150
t
PZL
t
PZH
High Impedance
Output Enable
Time
50
R
L
= 1 K
Ω
150
R
L
= 1 K
Ω
t
PLZ
t
PHZ
High Impedance
Output Disable
Time
50
R
L
= 1 K
Ω
CAPACITIVE CHARACTERISTICS
Symbol
Parameter
C
IN
C
OUT
Input Capacitance
bs
O
C
PD
et
l
o
Output
Capacitance
Power Dissipation
Capacitance (note
1)
ro
P
e
uc
d
V
CC
(V)
5.0
5.0
5.0
Test Condition
T
A
= 25°C
Min.
Typ.
5
10
31
Max.
10
s)
t(
O
-
so
b
te
le
ro
P
uc
d
s)
t(
ns
ns
ns
ns
Value
-40 to 85°C
Min.
Max.
10
-55 to 125°C
Min.
Max.
10
pF
pF
pF
Unit
1) C
PD
is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I
CC(opr)
= C
PD
x V
CC
x f
IN
+ I
CC
/8 (per circuit)
4/10
M74HC240
TEST CIRCUIT
TEST
t
PLH
, t
PHL
t
PZL
, t
PLZ
t
PZH
, t
PHZ
C
L
= 50pF/150pF or equivalent (includes jig and probe capacitance)
R
1
= 1KΩ or equivalent
R
T
= Z
OUT
of pulse generator (typically 50Ω)
WAVEFORM 1: PROPAGATION DELAY TIME
(f=1MHz; 50% duty cycle)
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t(
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-
so
b
te
le
ro
P
uc
d
Open
V
CC
GND
s)
t(
SWITCH
5/10
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