74HC251; 74HCT251
8-input multiplexer; 3-state
Rev. 5 — 15 July 2019
Product data sheet
1. General description
The 74HC251; 74HCT251 is an 8-bit multiplexer with eight binary inputs (I0 to I7), three select
inputs (S0 to S2) and an output enable input (OE). The select inputs select one of the eight binary
inputs and route it to the complementary outputs (Y and Y). A HIGH on OE causes the outputs to
assume a high-impedance OFF-state. Inputs include clamp diodes that enable the use of current
limiting resistors to interface inputs to voltages in excess of V
CC
.
2. Features and benefits
•
Input levels:
•
For 74HC251: CMOS level
•
For 74HCT251: TTL level
Low-power dissipation
Non-inverting data path
Specified in compliance with JEDEC standard no. 7A
ESD protection:
•
HBM JESD22-A114F exceeds 2000 V
•
MM JESD22-A115-A exceeds 200 V
Multiple package options
Specified from -40 °C to +85 °C and from -40 °C to +125 °C
•
•
•
•
•
•
•
3. Ordering information
Table 1. Ordering information
Type number
Package
Temperature range Name
74HC251D
74HCT251D
74HC251DB
74HCT251DB
74HC251PW
74HCT251PW
-40 °C to +125 °C
TSSOP16
-40 °C to +125 °C
SSOP16
-40 °C to +125 °C
SO16
Description
plastic small outline package; 16 leads;
body width 3.9 mm
plastic shrink small outline package; 16 leads;
body width 5.3 mm
plastic thin shrink small outline package;
16 leads; body width 4.4 mm
Version
SOT109-1
SOT338-1
SOT403-1
Nexperia
74HC251; 74HCT251
8-input multiplexer; 3-state
4. Functional diagram
4
I0
11
S0
S1
S2
OE
MULTIPLEXER
3
I1
2
I2
1
I3
15
I4
14
I5
13
I6
12
I7
4
I0
7
OE
3
I1
2
I2
1
I3
15
I4
14
I5
13
I6
12
I7
Y
Y
5
6
10
9
7
S0
11
S1
10
S2
9
aaa-008235
5
Y
6
Y
aaa-008236
Fig. 1.
Logic symbol
I7
I6
I5
I4
I3
I2
Fig. 2.
Functional diagram
Y
Y
I1
I0
S2
S1
S0
OE
aaa-008237
Fig. 3.
Logic diagram
74HC_HCT251
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2019. All rights reserved
Product data sheet
Rev. 5 — 15 July 2019
2 / 17
Nexperia
74HC251; 74HCT251
8-input multiplexer; 3-state
5. Pinning information
5.1. Pinning
74HC251
74HCT251
I3 1
I2 2
I1 3
I0 4
Y 5
Y 6
OE 7
GND 8
aaa-008239
16 V
CC
15 I4
14 I5
13 I6
12 I7
11 S0
10 S1
9
S2
74HC251
74HCT251
I3 1
I2
I1
I0
Y
OE
2
3
4
5
7
aaa-008240
16 V
CC
15 I4
14 I5
13 I6
12 I7
11 S0
10 S1
9
S2
Y 6
GND 8
Fig. 4.
Pin configuration SOT109-1 (SO16)
Fig. 5.
Pin configuration SOT338-1 (SSOP16)
and SOT403-1 (TSSOP16)
5.2. Pin description
Table 2. Pin description
Symbol
I0, I1, I2, I3, I4, I5, I6, I7
Y
Y
OE
GND
S0, S1, S2
V
CC
Pin
4, 3, 2, 1, 15, 14, 13, 12
5
6
7
8
11, 10, 9
16
Description
data inputs
multiplexer output
complementary multiplexer output
output enable input (active LOW)
ground (0 V)
common data select inputs
supply voltage
74HC_HCT251
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2019. All rights reserved
Product data sheet
Rev. 5 — 15 July 2019
3 / 17
Nexperia
74HC251; 74HCT251
8-input multiplexer; 3-state
6. Functional description
Table 3. Function table
H = HIGH voltage level; L = LOW voltage level; X = don’t care; Z = high-impedance OFF-state.
Input
OE
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
S2
X
L
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
S1
X
L
L
L
L
H
H
H
H
L
L
L
L
H
H
H
H
S0
X
L
L
H
H
L
L
H
H
L
L
H
H
L
L
H
H
I0
X
L
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
I1
X
X
X
L
H
X
X
X
X
X
X
X
X
X
X
X
X
I2
X
X
X
X
X
L
H
X
X
X
X
X
X
X
X
X
X
I3
X
X
X
X
X
X
X
L
H
X
X
X
X
X
X
X
X
I4
X
X
X
X
X
X
X
X
X
L
H
X
X
X
X
X
X
I5
X
X
X
X
X
X
X
X
X
X
X
L
H
X
X
X
X
I6
X
X
X
X
X
X
X
X
X
X
X
X
X
L
H
X
X
I7
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
L
H
Output
Y
Z
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
Y
Z
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
7. Limiting values
Table 4. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to GND (ground = 0 V).
Symbol Parameter
V
CC
I
IK
I
OK
I
O
I
CC
I
GND
T
stg
P
tot
[1]
[2]
[3]
Conditions
V
I
< -0.5 V or V
I
> V
CC
+ 0.5 V
V
O
< -0.5 V or V
O
> V
CC
+ 0.5 V
V
O
= -0.5 V to (V
CC
+ 0.5 V)
Min
-0.5
-
-
-
-
-50
-65
Max
+7
±20
±20
±25
+50
-
+150
500
Unit
V
mA
mA
mA
mA
mA
°C
mW
supply voltage
input clamping current
output clamping current
output current
supply current
ground current
storage temperature
total power dissipation
T
amb
= -40 °C to +125 °C
[1][2][3]
-
For SOT109-1 (SO16) packages: P
tot
derates linearly with 12.4 mW/K above 110 °C.
For SOT338-1 (SSOP16) packages: P
tot
derates linearly with 8.5 mW/K above 91 °C.
For SOT403-1 (TSSOP16) packages: P
tot
derates linearly with 8.5 mW/K above 91 °C.
74HC_HCT251
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2019. All rights reserved
Product data sheet
Rev. 5 — 15 July 2019
4 / 17
Nexperia
74HC251; 74HCT251
8-input multiplexer; 3-state
8. Recommended operating conditions
Table 5. Recommended operating conditions
Voltages are referenced to GND (ground = 0 V)
Symbol Parameter
V
CC
V
I
V
O
T
amb
Δt/ΔV
supply voltage
input voltage
output voltage
ambient temperature
input transition rise and fall rate
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
Conditions
Min
2.0
0
0
-40
-
-
-
74HC251
Typ
5.0
-
-
+25
-
1.67
-
Max
6.0
V
CC
V
CC
+125
625
139
83
Min
4.5
0
0
-40
-
-
-
74HCT251
Typ
5.0
-
-
+25
-
1.67
-
Max
5.5
V
CC
V
CC
+125
-
139
-
V
V
V
°C
ns/V
ns/V
ns/V
Unit
9. Static characteristics
Table 6. Static characteristics
At recommended operating conditions; voltages are referenced to GND (ground = 0 V).
Symbol Parameter
Conditions
Min
74HC251
V
IH
HIGH-level
input voltage
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
V
IL
LOW-level
input voltage
V
CC
= 2.0 V
V
CC
= 4.5 V
V
CC
= 6.0 V
V
OH
HIGH-level
output voltage
V
I
= V
IH
or V
IL
I
O
= -20 μA; V
CC
= 2.0 V
I
O
= -20 μA; V
CC
= 4.5 V
I
O
= -20 μA; V
CC
= 6.0 V
I
O
= -4.0 mA; V
CC
= 4.5 V
I
O
= -5.2 mA; V
CC
= 6.0 V
V
OL
LOW-level
output voltage
V
I
= V
IH
or V
IL
I
O
= 20 μA; V
CC
= 2.0 V
I
O
= 20 μA; V
CC
= 4.5 V
I
O
= 20 μA; V
CC
= 6.0 V
I
O
= 4.0 mA; V
CC
= 4.5 V
I
O
= 5.2 mA; V
CC
= 6.0 V
-
-
-
-
-
0
0
0
0.15
0.16
0.1
0.1
0.1
0.26
0.26
-
-
-
-
-
0.1
0.1
0.1
0.33
0.33
-
-
-
-
-
0.1
0.1
0.1
0.4
0.4
V
V
V
V
V
1.9
4.4
5.9
3.98
5.48
2.0
4.5
6.0
4.32
5.81
-
-
-
-
-
1.9
4.4
5.9
3.84
5.34
-
-
-
-
-
1.9
4.4
5.9
3.7
5.2
-
-
-
-
-
V
V
V
V
V
1.5
3.15
4.2
-
-
-
1.2
2.4
3.2
0.8
2.1
2.8
-
-
-
0.5
1.35
1.8
1.5
3.15
4.2
-
-
-
-
-
-
0.5
1.35
1.8
1.5
3.15
4.2
-
-
-
-
-
-
0.5
1.35
1.8
V
V
V
V
V
V
25 °C
Typ
Max
-40 °C to
+85 °C
Min
Max
-40 °C to
+125 °C
Min
Max
Unit
74HC_HCT251
All information provided in this document is subject to legal disclaimers.
©
Nexperia B.V. 2019. All rights reserved
Product data sheet
Rev. 5 — 15 July 2019
5 / 17