INTEGRATED CIRCUITS
DATA SHEET
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/HCT7245
Octal bus Schmitt-trigger
transceiver; 3-state
Product specification
File under Integrated Circuits, IC06
December 1990
Philips Semiconductors
Product specification
Octal bus Schmitt-trigger transceiver;
3-state
FEATURES
•
Octal bidirectional bus interface
•
Non-inverting 3-state outputs
•
Output capability: bus driver
•
I
CC
category: MSI
•
Schmitt-trigger action on all data
inputs
GENERAL DESCRIPTION
The 74HC/HCT7245 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.
The 74HC/HCT7245 are octal
transceivers featuring non-inverting
3-state bus compatible outputs in
both send and receive directions. The
“7245” features an output enable
(OE) input for easy cascading and a
send/receive input (DIR) for direction
control. OE controls the outputs so
that the buses are effectively isolated.
The 74HC/HCT7245 have
Schmitt-trigger inputs. These inputs
are capable of transforming slowly
changing input signals into sharply
defined jitter-free output signals.
74HC/HCT7245
The “7245” is identical to the “245” but
has hysteresis on the data inputs.
FUNCTION TABLE
INPUTS
OE
L
L
H
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
Z = high impedance OFF-state
DIR
L
H
X
INPUTS/OUTPUTS
A
n
A=B
inputs
Z
B
n
inputs
B=A
Z
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
°C;
t
r
= t
f
= 6 ns
TYPICAL
SYMBOL
t
PHL
/ t
PLH
C
I
C
I/O
C
PD
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
µW):
P
D
= C
PD
×
V
CC2
×
f
i
+ ∑
(C
L
×
V
CC2
×
f
o
) where:
f
i
= input frequency in MHz
f
o
= output frequency in MHz
∑
(C
L
×
V
CC2
×
f
o
) = sum of outputs
C
L
= output load capacitance in pF
V
CC
= supply voltage in V
2. For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
−
1.5 V
ORDERING INFORMATION
See
“74HC/HCT/HCU/HCMOS Logic Package Information”.
PARAMETER
propagation delay A
n
to B
n
input capacitance
input/output capacitance
power dissipation capacitance per transceiver
notes 1 and 2
CONDITIONS
HC
C
L
= 15 pF; V
CC
= 5 V
8
3.5
10
40
HCT
12
3.5
10
40
ns
pF
pF
pF
UNIT
December 1990
2
Philips Semiconductors
Product specification
Octal bus Schmitt-trigger transceiver;
3-state
PIN DESCRIPTION
PIN NO.
1
2, 3, 4, 5, 6, 7, 8, 9
10
18, 17, 16, 15, 14, 13, 12, 11
19
20
SYMBOL
DIR
A
0
to A
7
GND
B
0
to B
7
OE
V
CC
NAME AND FUNCTION
direction control
data inputs/outputs
ground (0 V)
data inputs/outputs
74HC/HCT7245
output enable input (active LOW)
positive supply voltage
alfpage
ge
DIR
A0
A1
A2
A3
A4
A5
A6
A7
1
2
3
4
5
20 VCC
19 OE
19
OE
age
19
1
1
18 B 0
17 B 1
16 B 2
2
DIR
G3
3EN1
3EN2
A0
B0
18
2
3
4
5
1
2
18
17
16
15
14
13
12
11
MBA404
7245
6
7
8
9
15 B 3
14 B 4
13 B 5
12 B 6
11 B 7
MBA327
MBA330
9
A7
B7
6
11
7
8
9
GND 10
Fig.1 Pin configuration.
Fig.2 Functional diagram.
Fig.3 IEC logic symbol.
December 1990
3
Philips Semiconductors
Product specification
Octal bus Schmitt-trigger transceiver;
3-state
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: bus driver
I
CC
category: MSI
TRANSFER CHARACTERISTICS FOR 74HC
Voltages are referred to GND (ground = 0 V)
T
amb
(°C)
74HC
SYMBOL PARAMETER
+25
−40
to
+85
−40
to
+125
74HC/HCT7245
TEST CONDITIONS
UNIT V
CC
WAVEFORMS
(V)
V
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
Figs. 4 and 5
min. typ. max. min. max. min. max.
V
T+
positive-going threshold
1.50
3.15
4.20
0.30
1.35
1.80
0.1
0.25
0.3
0.2
0.4
0.5
0.30
1.35
1.80
0.1
0.25
0.3
1.50
3.15
4.20
0.30
1.35
1.80
0.1
0.25
0.3
1.50
3.15
4.20
V
T−
negative-going threshold
V
Figs. 4 and 5
V
H
hysteresis (V
T+
−
V
T−
)
V
Figs. 4 and 5
AC CHARACTERISTICS FOR 74HC
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
T
amb
(°C)
74HC
SYMBOL
PARAMETER
+25
−40
to
+85
−40
to
+125
max.
150
30
26
240
48
41
240
48
41
90
18
15
ns
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
2.0
4.5
6.0
Fig.7
UNIT V
CC
WAVEFORMS
(V)
TEST CONDITIONS
min. typ. max. min. max. min.
t
PHL
/ t
PLH
propagation delay
A
n
to B
n
;
B
n
to A
n
3-state output enable time
OE to A
n
;
OE to B
n
3-state output disable time
OE to A
n
;
OE to B
n
output transition time
33
12
10
47
17
14
52
19
16
14
5
4
100
20
17
160
32
27
160
32
27
60
12
10
125
25
21
200
40
34
200
40
34
75
15
13
t
PZH
/ t
PZL
ns
Fig.7
t
PHZ
/ t
PLZ
ns
Fig.7
t
THL
/ t
TLH
ns
Fig.7
December 1990
4
Philips Semiconductors
Product specification
Octal bus Schmitt-trigger transceiver;
3-state
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: bus driver
I
CC
category: MSI
Note to HCT types
74HC/HCT7245
The value of additional quiescent supply current (∆I
CC
) for a unit load of 1 is given in the family specifications.
To determine
∆I
CC
per input, multiply this value by the unit load coefficient shown in the table below.
INPUT
A
n
B
n
OE
DIR
UNIT LOAD COEFFICIENT
0.33
0.33
1.50
1.00
TRANSFER CHARACTERISTICS FOR 74HCT
Voltages are referred to GND (ground = 0 V)
T
amb
(°C)
74HCT
SYMBOL PARAMETER
+25
−40
to
+85
−40
to
+125
UNIT V
CC
WAVEFORMS
(V)
V
V
V
4.5
5.5
4.5
5.5
4.5
5.5
Figs. 4 and 5
Figs. 4 and 5
Figs. 4 and 5
TEST CONDITIONS
min. typ. max. min. max. min. max.
V
T+
V
T−
V
H
positive-going threshold
negative-going threshold
hysteresis (V
T+
−
V
T−
)
0.7
0.8
0.17
0.17
0.23
0.23
2.0
2.1
0.64
0.74
2.0
2.1
0.6
0.7
2.0
2.1
December 1990
5
Embedded System
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