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INTEGRATED CIRCUITS
DATA SH EET
For a complete data sheet, please also download:
•The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
•The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
•The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
74HC/HCT244
Octal buffer/line driver; 3-state
Product specification
File under Integrated Circuits, IC06
December 1990
Page 2
Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
FEATURES
• Output capability: bus driver
• ICC category: MSI
The 74HC/HCT244 are octal non-inverting buffer/line
drivers with 3-state outputs. The 3-state outputs are
controlled by the output enable inputs 1
A HIGH on nOE causes the outputs to assume a high
impedance OFF-state. The “244” is identical to the “240”
GENERAL DESCRIPTION
but has non-inverting outputs.
The 74HC/HCT244 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
QUICK REFERENCE DATA
GND = 0 V; T
=25°C; tr=tf= 6 ns
amb
SYMBOL PARAMETER CONDITIONS
t
PHL
/ t
PLH
propagation delay
CL= 15 pF; VCC=5V 9 11 ns
1An to 1Yn;
C
C
I
PD
2An to 2Y
input capacitance 3.5 3.5 pF
power dissipation capacitance per buffer notes 1 and 2 35 35 pF
n
Notes
1. C
is used to determine the dynamic power dissipation (PD in µW):
PD
PD=CPD× V
2
× fi+∑ (CL× V
CC
2
× fo) where:
CC
fi= input frequency in MHz
fo= output frequency in MHz
∑ (CL× V
2
× fo) = sum of outputs
CC
CL= output load capacitance in pF
VCC= supply voltage in V
2. For HC the condition is VI= GND to V
CC
For HCT the condition is VI= GND to VCC− 1.5 V
OE and 2OE.
TYPICAL
UNIT
HC HCT
ORDERING INFORMATION
“74HC/HCT/HCU/HCMOS Logic Package Information”
See
December 1990 2
.
Page 3
Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
11
2, 4, 6, 8 1A
3, 5, 7, 9 2Y
10 GND ground (0 V)
17, 15, 13, 11 2A
18, 16, 14, 12 1Y
19 2
20 V
OE output enable input (active LOW)
to 1A
0
to 2Y
0
to 2A
0
to 1Y
0
3
3
3
3
data inputs
bus outputs
data inputs
bus outputs
OE output enable input (active LOW)
CC
positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.
December 1990 3
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Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
FUNCTION TABLE
INPUTS OUTPUT
OE nA
n
L
L
H
Note
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
Z = high impedance OFF-state
n
L
H
X
nY
n
L
H
Z
Fig.4 Functional diagram.
December 1990 4
Page 5
Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”
Output capability: bus driver
ICC category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; t
= 6 ns; CL=50pF
r=tf
SYMBOL PARAMETER
t
PHL
t
PZH
t
PHZ
t
THL
/ t
/ t
/ t
/ t
propagation delay
PLH
1An to 1Y
2An to 2Y
3-state output enable time
PZL
1OE to 1Y
2OE to 2Y
3-state output disable time
PLZ
1OE to 1Y
2OE to 2Y
output transition time 14
TLH
n;
n
n;
n
n;
n
(°C)
T
amb
74HC
+25 −40 to +85 −40 to +125
min. typ. max. min. max. min. max.
30
11
9
36
13
10
39
14
11
5
4
110
22
19
150
30
26
150
30
26
60
12
10
145
28
24
190
38
33
190
38
33
75
15
13
165
33
28
225
45
38
225
45
38
90
18
15
.
UNIT
ns 2.0
ns 2.0
ns 2.0
ns 2.0
TEST CONDITIONS
WAVEFORMS
V
CC
(V)
Fig.5
4.5
6.0
Fig.6
4.5
6.0
Fig.6
4.5
6.0
Fig.5
4.5
6.0
December 1990 5
Page 6
Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”
.
Output capability: bus driver
ICC category: MSI
Note to HCT types
The value of additional quiescent supply current (∆I
) for a unit load of 1 is given in the family specifications.
CC
To determine ∆ICC per input, multiply this value by the unit load coefficient shown in the table below.
INPUT UNIT LOAD COEFFICIENT
1A
2A
1OE
2OE
n
n
0.70
0.70
0.70
0.70
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; tr=tf= 6 ns; CL=50pF
T
amb
(°C)
TEST CONDITIONS
74HCT
SYMBOL PARAMETER
+25 −40 to +85 −40 to +125
UNIT
V
(V)
min. typ. max. min. max. min. max.
t
PHL
t
PZH
t
PHZ
t
THL
/ t
/ t
/ t
/ t
propagation delay
PLH
1An to 1Y
2An to 2Y
3-state output enable time
PZL
1OE to 1Y
2OE to 2Y
3-state output disable time
PLZ
1OE to 1Y
2OE to 2Y
output transition time 5 12 15 18 ns 4.5 Fig.5
TLH
n;
n
n;
n
n;
n
13 22 28 33 ns 4.5 Fig.5
15 30 38 45 ns 4.5 Fig.6
15 25 31 38 ns 4.5 Fig.6
WAVEFORMS
CC
December 1990 6
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Philips Semiconductors Product specification
Octal buffer/line driver; 3-state 74HC/HCT244
AC WAVEFORMS
(1) HC : VM= 50%; VI= GND to VCC.
HCT : V
= 1.3 V; VI= GND to 3 V.
M
Fig.5 Waveforms showing the input (1An, 2An) to output (1Yn, 2Yn) propagation delays and the output transition
times.
(1) HC : VM= 50%; VI= GND to VCC.
HCT : V
= 1.3 V; VI= GND to 3 V.
M
Fig.6 Waveforms showing the 3-state enable and disable times.
PACKAGE OUTLINES
“74HC/HCT/HCU/HCMOS Logic Package Outlines”
See
.
December 1990 7
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