M54/74HCT245/640/643
M54/74HCT245/640/643
October 1993
HCT640 INVERTING, HCT643 INVERTING/NON INVERTING
OCTAL BUS TRANSCEIVER (3-STATE): HCT245 NON INVERTING
B1R
(Plastic Package)
ORDER CODES :
M54HCTXXXF1R
M74HCTXXXM1R
M74HCTXXXB1R
M74HCTXXXC1R
F1R
(Ceramic Package)
M1R
(Micro Package)
C1R
(Chip Carrier)
PIN CONNECTION (top view)
.
HIGH SPEED
t
PD
= 10 ns (TYP.) at V
CC
= 5V
.
LOW POWER DISSIPATION
I
CC
= 4
A (MAX.) at T
A
= 25
o
C
.
COMPATIBLE WITH TTL OUTPUTS
V
IH
= 2V (MIN.) V
IL
= 0.8V (MAX.)
.
OUTPUT DRIVE CAPABILITY
15 LSTTL LOADS
.
SYMMETRICAL OUTPUT IMPEDANCE
|I
OH
| = I
OL
= 6 mA (MIN)
.
BALANCED PROPAGATION DELAYS
t
PLH
= t
PHL
.
PIN AND FUNCTION COMPATIBLE
WITH 54/74LS245/640/643
DESCRIPTION
The M54/74HCT245, HCT640 and HCT643 utilise
silicon gate C
2
MOS technology to achive operating
speeds eqivalent to LSTTL devices.
Along with the low power dissipation and high noise
immunity of standad CMOS integrated circuit, it
possesses the capability to drive 15 LSTTL loads.
These IC's are intended for two-way asynchronous
communication between data buses, and the
direction of data trasmission is determined by DIR
input. The enable input (G) can be used to disable
the device so that the buses are effectively isolated.
All input are equipped with protection circuits
against static discharge and transient discharge.
These integrated circuits have input and output
characteristics that are fully compatible with 54/74
LSTTL logic families. M54/74HCT devices are
designed to directly interface HSC
2
MOS systems
with TTL and NMOS components. They are also
plug in replacements for LSTTL devices giving a
reduction of power consumption.
IT IS PROHIBITED TO APPLY A SIGNAL TO A
BUS TERMINAL WHEN IT IS IN OUTPUT MODE
AND WHEN A BUS THERMINAL IS FLOATING
(HIGH IMPEDANCE STATE), IT IS REQUESTED
TO FIX THE INPUT LEVEL BY MEANS OF
EXTERNAL
PULL
DOWN
OR
PULL
UP
RESISTOR.
HCT245
HCT640
HCT643
1/11
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No
SYMBOL
NAME AND FUNCTION
1
DIR
Directional Control
2, 3, 4, 5,
6, 7, 8, 9
A1 to A8
Data Inputs/Outputs
18, 17, 16,
15, 14, 13,
12, 11
B1 to B8
Data Inputs/Outputs
19
G
Output Enabel Input
(Active LOW)
10
GND
Ground (0V)
20
V
CC
Positive Supply Voltage
IEC LOGIC SYMBOLS
TRUTH TABLE
INPUT
FUNCTION
OUTPUT
G
DIR
A BUS
B BUS
HCT245
HCT640
HCT643
L
L
OUTPUT
INPUT
A = B
A = B
A = B
L
H
INPUT
OUTPUT
B = A
B = A
B = A
H
X
Z
Z
Z
Z
Z
X: "H" or "L"
Z: High impedance
HCT245
HCT640
HCT643
M54/M74HCT245/640/643
2/11
LOGIC DIAGRAM (HCT640)
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
-0.5 to +7
V
V
I
DC Input Voltage
-0.5 to V
CC
+ 0.5
V
V
O
DC Output Voltage
-0.5 to V
CC
+ 0.5
V
I
IK
DC Input Diode Current
20
mA
I
OK
DC Output Diode Current
20
mA
I
O
DC Output Source Sink Current Per Output Pin
35
mA
I
CC
or I
GND
DC V
CC
or Ground Current
70
mA
P
D
Power Dissipation
500 (*)
mW
T
stg
Storage Temperature
-65 to +150
o
C
T
L
Lead Temperature (10 sec)
300
o
C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied.
(*) 500 mW:
65
o
C derate to 300 mW by 10mW/
o
C: 65
o
C to 85
o
C
NOTE: IN CASE OF HCT245 OR HCT643, INPUT INVERTERS MARKED* AT A BUS AND B BUS ARE ELIMINATED RESPECTIVELY
M54/M74HCT245/640/643
3/11
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Value
Unit
V
CC
Supply Voltage
4.5 to 5.5
V
V
I
Input Voltage
0 to V
CC
V
V
O
Output Voltage
0 to V
CC
V
T
op
Operating Temperature: M54HC Series
M74HC Series
-55 to +125
-40 to +85
o
C
o
C
t
r
, t
f
Input Rise and Fall Time (V
CC
= 4.5 to 5.5V)
0 to 500
ns
DC SPECIFICATIONS
Symbol
Parameter
Test Conditions
Value
Unit
V
CC
(V)
T
A
= 25
o
C
54HC and 74HC
-40 to 85
o
C
74HC
-55 to 125
o
C
54HC
Min.
Typ.
Max.
Min.
Max.
Min.
Max.
V
IH
High Level Input
Voltage
4.5
to
5.5
2.0
2.0
2.0
V
V
IL
Low Level Input
Voltage
4.5
to
5.5
0.8
0.8
0.8
V
V
OH
High Level
Output Voltage
4.5
V
I
=
V
IH
or
V
IL
I
O
=-20
A
4.4
4.5
4.4
4.4
V
I
O
=-6.0 mA
4.18
4.31
4.13
4.10
V
OL
Low Level Output
Voltage
4.5
V
I
=
V
IH
or
V
IL
I
O
= 20
A
0.0
0.1
0.1
0.1
V
I
O
= 6.0 mA
0.17
0.26
0.33
0.4
I
I
Input Leakage
Current
5.5
V
I
= V
CC
or GND
0.1
1
1
A
I
OZ
3 State Output
Off State Current
5.5
V
I
= V
CC
or GND
0.5
5.0
10
A
I
CC
Quiescent Supply
Current
5.5
V
I
= V
CC
or GND
4
40
80
A
I
CC
Additional worst
case supply
current
5.5
Per Input pin
V
I
= 0.5V or
V
I
= 2.4V
Other Inputs at
V
CC
or GND
I
O
= 0
2.0
2.9
3.0
mA
M54/M74HCT245/640/643
4/11
AC ELECTRICAL CHARACTERISTICS (C
L
= 50 pF, Input t
r
= t
f
= 6 ns)
Symbol
Parameter
Test Conditions
Value
Unit
V
CC
(V)
C
L
(pF)
T
A
= 25
o
C
54HC and 74HC
-40 to 85
o
C
74HC
-55 to 125
o
C
54HC
Min.
Typ.
Max.
Min.
Max.
Min.
Max.
t
TLH
t
THL
Output Transition
Time
4.5
50
7
12
15
18
ns
t
PLH
t
PHL
Propagation
Delay Time
4.5
50
13
22
28
33
ns
4.5
150
18
30
38
45
ns
t
PZL
t
PZH
Output Enable
Time
4.5
50
R
L
= 1K
19
30
38
45
ns
4.5
150
R
L
= 1K
24
38
48
57
ns
t
PLZ
t
PHZ
Output Disable
Time
4.5
50
R
L
= 1K
17
30
38
45
ns
C
IN
Input Capacitance
DIR, G
5
10
10
10
pF
C
I/OUT
Output
Capacitance
An, Bn
13
pF
C
PD
(*)
Power Dissipation
Capacitance
HCT245
HCT640/643
41
39
pF
(*) 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 operting current can be obtained by the following equation. I
CC
(opr) = C
PD
V
CC
f
IN
+ I
CC
/8 (per circuit)
SWITCHING CHARACTERISTICS TEST WAVEFORM
M54/M74HCT245/640/643
5/11
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