M54/74HCT125
M54/74HCT126
October 1993
QUAD BUS BUFFERS (3-STATE)
B1R
(Plastic Package)
ORDER CODES :
M54HCTXXXF1R
M74HCTXXXM1R
M74HCTXXXB1R
M74HCTXXXC1R
F1R
(Ceramic Package)
M1R
(Micro Package)
C1R
(Chip Carrier)
PIN CONNECTIONS (top view)
NC =
No Internal
Connection
INPUT AND OUTPUT EQUIVALENT CIRCUIT
DESCRIPTION
.
HIGH SPEED
t
PD
= 12 ns (TYP.) AT V
CC
= 5 V
.
LOW POWER DISSIPATION
I
CC
= 4
A (MAX.) AT 25
C
.
OUTPUT DRIVE CAPABILITY
15 LSTTL LOADS
.
BALANCED PROPAGATION DELAYS
t
PLH
= t
PHL
.
SYMMETRICAL OUTPUT IMPEDANCE
I
OL
=
I
OH
= 6 mA (MIN.)
.
COMPATIBLE WITH TTL OUTPUTS
V
IH
= 2V (MIN.) V
IL
= 0.8V (MAX)
.
PIN AND FUNCTION COMPATIBLE
WITH 54/74LS125/126
The M54/74HCT125/126 are high speed CMOS
QUAD BUS BUFFER (3-STATE) FABRICATED IN
SILICON GATE C
2
MOS technology. They have the
same high speed performance of LSTTL combined
with true CMOS low power consumption. These de-
vices require the same 3-STATE control input G to
be taken high to make the output go into the high im-
pedance state.This integrated circuit has 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 sys-
tems with TTL and NMOS components. They are
also plug in replacements for LSTTL devices giving
a reduction of power consumption. All inputs are
equipped with protection circuits against static dis-
charge and transient excess voltage.
HCT125
HCT126
1/10
CIRCUIT DIAGRAM
HCT125
HCT126
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 tothe device may occur. Functional operation under these conditions is not implied.
(*) 500 mW:
65
o
C derate to 300 mW by 10mW/
o
C: 65
o
C to 85
o
C
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
M54/M74HCT125/126
3/10
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
CC
Quiescent Supply
Current
5.5
V
I
= V
CC
or GND
4
40
80
A
I
OZ
3 State Output
Off State Current
6.0
V
I
= V
IH
or V
IL
V
O
= V
CC
or GND
0.5
5
10
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
AC ELECTRICAL CHARACTERISTICS (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
21
26
32
ns
4.5
150
17
27
34
41
ns
t
PZL
t
PZH
3 State Output
Enable Time
4.5
50
R
L
= 1 K
15
24
30
36
ns
4.5
150
R
L
= 1 K
19
30
38
45
ns
t
PLZ
t
PHZ
3 State Output
Disable Time
4.5
50
R
L
= 1 K
17
24
30
36
ns
C
IN
Input Capacitance
5
10
10
10
pF
C
PD
(*)
Power Dissipation
Capacitance
56
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
M54/M74HCT125/126
4/10
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