1/9August 2001
■HIGH SPE ED:
tPD = 15 ns (TYP.) at VCC = 4.5V
■LOW POWER DISSIPATION:
ICC = 4µA(MAX.) at TA=25°C
■COMPAT I B L E WITH TTL OU TP U TS :
VIH = 2V (MIN.) VIL = 0.8V (MAX)
■BALANCED PROPAGATION DELAYS:
tPLH ≅ tPHL
■SYMMETRICAL OUTPUT IMPEDANCE:
|IOH| = IOL = 6mA (MIN)
■PIN AND FUNCTION COMPAT IBLE WITH
74 SERIES 240
DESCRIPTION
The 74HCT240 is an advanced high-speed
CMOS OCTAL BUS BUFFER (3-STATE)
fabricated with silicon gate C2MOS technolog y.
G control input governs four BUS BUFFE Rs.
All inputs are equipped with protection circuits
against static discharge and transient excess
voltage.
M74HCT240
OCTAL BUS BUFF ER
WITH 3 STATE OUT PUTS (INVERTED)
PIN CONNECTION AND IEC LOGIC SYMBOLS
ORDER CODES
PACKAGE TUBE T & R
DIP M74HCT240B1R
SOP M74HCT240M1R M74HCT240RM13TR
TSSOP M74HCT240TTR
TSSOPDIP SOP
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INPUT AND OUT PUT EQUIVALENT CIRCUIT PIN DESCRIPTION
TRUTH TABLE
X : Don’t Care
Z : Hi gh Imp edance
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functi onal operation under thes e conditions is
not implie d
(* ) 500mW at 65 °C; derat e to 300mW by 10mW/°C from 65°C to 85°C
RECOMMENDE D OPERATING CONDITIONS
PIN No SYMBOL NAME AND FUNCTION
11G
Output Enable Input
2, 4, 6, 8 1A1 to 1A4 Data Inputs
9, 7, 5, 3 2Y1 to 2Y4 Data Outputs
11, 13, 15,
17 2A1 to 2A4 Data Inputs
18, 16, 14,
12 1Y1 to 1Y4 Data Outputs
19 2G Output Enable Input
10 GND Ground (0V)
20 VCC Positive Supply Voltage
INPUTS OUTPUT
GAn Yn
LLH
LHL
HXZ
Symbol Parameter Value Unit
VCC Supply Voltage -0.5 to +7 V
VIDC Input Voltage -0.5 to VCC + 0.5 V
VODC Output Volta ge -0.5 to VCC + 0.5 V
IIK DC Input Diode Current ± 20 mA
IOK DC Output Diode Current ± 20 mA
IODC Output Current ± 35 mA
ICC or IGND DC VCC or Ground Curre nt ± 70 mA
PDPower Dissipation 500(*) mW
Tstg Storage Temperature -65 to +150 °C
TLLead Temperature (10 sec) 300 °C
Symbol Parameter Value Unit
VCC Supply Voltage 4.5 to 5.5 V
VIInput Voltage 0 to VCC V
VOOutput Voltage 0 to VCC V
Top Operating Temperature -55 to 125 °C
tr, tfInput Rise and Fall Time (VCC = 4.5 to 5.5V) 0 to 500 ns
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DC SPE CIFICATI ONS
AC EL ECTRI CAL CHARACTERISTICS (CL = 50 pF, Input tr = tf = 6 ns)
Symbol Parameter
Test Condition Value
Unit
VCC
(V)
TA = 25°C -40 to 85°C -55 to 125°C
Min. Typ. Max. Min. Max. Min. Max.
VIH High Level Input
Voltage 4.5
to
5.5 2.0 2.0 2.0 V
VIL Low Level Input
Voltage 4.5
to
5.5 0.8 0.8 0.8 V
VOH High Level Output
Voltage 4.5 IO=-20 µA4.4 4.5 4.4 4.4 V
IO=-6.0 mA 4.18 4.31 4.13 4.10
VOL Low Level Output
Voltage 4.5 IO=20 µA0.0 0.1 0.1 0.1 V
IO=6.0 mA 0.17 0.26 0.33 0.40
IIInput Leakage
Current 5.5 VI = VCC or GND ± 0.1 ± 1 ± 1 µA
IOZ High Impedance
Output Leakage
Current 5.5 VI = VIH or VIL
VO = VCC or GND ± 0.5 ± 5 ± 10 µA
ICC Quiescent Supply
Current 5.5 VI = VCC or GND 44080µA
∆ ICC Additional Worst
Case Supply
Current
5.5 Per Input pin
VI = 0.5V or
VI = 2.4V
Other Inputs at
VCC or GND
2.0 2.9 3.0 mA
Symbol Parameter
Test Condition Value
Unit
VCC
(V) CL
(pF)
TA = 25°C -40 to 85°C -55 to 125°C
Min. Typ. Max. Min. Max. Min. Max.
tTLH tTHL Output Transition
Time 4.5 50 7 12 15 18 ns
tPLH tPHL Propagation Delay
Time 4.5 50 15 22 28 33 ns
4.5 150 21 30 38 45
tPZL tPZH Output Enable
Time 4.5 50 RL = 1 KΩ17 30 38 45 ns
4.5 150 23 38 48 57
tPLZ tPHZ Output Disable
Time 4.5 50 RL = 1 KΩ16 30 38 45 ns
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CAPACITIVE CHARACT ERISTICS
1) C PD is defined as the value of the IC’s internal equivalent capacitance which is calculated f rom the operating current consumption without
load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. ICC(opr) = CPD x VCC x fIN + ICC/8 (per circuit)
TEST CIRCUIT
CL = 50p F/150pF or equiv al ent (includes ji g and probe capacitance )
R1 = 1KΩ or equivalent
RT = ZOUT of pulse ge nerator (typically 50Ω)
Symbol Parameter
Test Condition Value
Unit
VCC
(V)
TA = 25°C -40 to 85°C -55 to 125°C
Min. Typ. Max. Min. Max. Min. Max.
CIN Input Capacitance 5101010pF
C
OUT Output
Capacitance 10 pF
CPD Power Dissipation
Capacitance (note
1) 33 pF
TEST SWITCH
tPLH, tPHL Open
tPZL, tPLZ VCC
tPZH, tPHZ GND
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WAVE FORM 1 : PROPAGATION DELAY TIMES (f=1MHz; 50% duty cycle)
WAVE FORM 2 : OUTPUT AND ENABLE TIMES (f= 1 MHz; 50% d u ty cyc l e)
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DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
a1 0.254 0.010
B 1.39 1.65 0.055 0.065
b 0.45 0.018
b1 0.25 0.010
D 25.4 1.000
E 8.5 0.335
e 2.54 0.100
e3 22.86 0.900
F 7.1 0.280
I 3.93 0.155
L 3.3 0.130
Z 1.34 0.053
Plastic DIP-20 (0.25) MECHANICAL DATA
P001J
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DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 2.65 0.104
a1 0.1 0.2 0.004 0.008
a2 2.45 0.096
b 0.35 0.49 0.014 0.019
b1 0.23 0.32 0.009 0.012
C 0.5 0.020
c1 45° (typ.)
D 12.60 13.00 0.496 0.512
E 10.00 10.65 0.393 0.419
e 1.27 0.050
e3 11.43 0.450
F 7.40 7.60 0.291 0.300
L 0.50 1.27 0.020 0.050
M 0.75 0.029
S8° (max.)
SO-20 MECHANICAL DATA
PO13L
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DIM. mm. inch
MIN. TYP MAX. MIN. TYP. MAX.
A 1.2 0.047
A1 0.05 0.15 0.002 0.004 0.006
A2 0.8 1 1.05 0.031 0.039 0.041
b 0.19 0.30 0.007 0.012
c 0.09 0.20 0.004 0.0089
D 6.4 6.5 6.6 0.252 0.256 0.260
E 6.2 6.4 6.6 0.244 0.252 0.260
E1 4.3 4.4 4.48 0.169 0.173 0.176
e 0.65 BSC 0.0256 BSC
K0° 8°0° 8°
L 0.45 0.60 0.75 0.018 0.024 0.030
TSSOP20 MECHANICAL DATA
cE
b
A2
A
E1
D
1
PIN 1 IDENTIFICATION
A1 L
K
e
0087225C
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M74HCT240
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conseque nces of use of such i nformation nor for any infringement of patents or ot her rights of third part ies which may result from
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