DATA SH EET
Product specification
File under Integrated Circuits, IC06 December 1990
INTEGRATED CIRCUITS
74HC/HCT251
8-input multiplexer; 3-state
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
December 1990 2
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
FEATURES
•True and complement outputs
•Both outputs are 3-state for further multiplexer
expansion
•Multifunction capability
•Permits multiplexing from n-lines to one line
•Output capability: standard
•ICC category: MSI
GENERAL DESCRIPTION
The 74HC/HCT251 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/HCT251 are the logic implementations of
single-pole 8-position switches with the state of three
select inputs (S0,S
1
,S
2
) controlling the switch positions.
Assertion (Y) and negation (Y) outputs are both provided.
The output enable input (OE) is active LOW. The logic
function provided at the output, when activated, is:
Y=OE.(I0.S0.S1.S2 + I1.S0.S1.S2+
+I2.S0.S1.S2+I3.S0.S1.S2+
+I4.S0.S1.S2+I5.S0.S1.S2+
+I6.S0.S1.S2+I7.S0.S1.S2)
Both outputs are in the high impedance OFF-state (Z)
when the output enable input is HIGH, allowing multiplexer
expansion by tying the outputs.
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr= tf= 6 ns
Notes
1. CPD is used to determine the dynamic power dissipation (PDin µW):
PD= CPD ×VCC2×fi+∑(CL×VCC2×fo) where:
fi= input frequency in MHz
fo= output frequency in MHz
∑(CL×VCC2×fo) = sum of outputs
CL= output load capacitance in pF
VCC = supply voltage in V
2. For HC the condition is VI= GND to VCC
For HCT the condition is VI= GND to VCC −1.5 V
ORDERING INFORMATION
See
“74HC/HCT/HCU/HCMOS Logic Package Information”
.
SYMBOL PARAMETER CONDITIONS TYPICAL UNIT
HC HCT
tPHL/ tPLH propagation delay CL= 15 pF; VCC = 5 V
Into Y 15 19 ns
Into Y1719ns
S
n
to Y 20 20 ns
Snto Y2121ns
C
I
input capacitance 3.5 3.5 pF
CPD power dissipation capacitance per package notes 1 and 2 44 46 pF
December 1990 3
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
4, 3, 2, 1, 15, 14, 13, 12 I0to I7multiplexer inputs
5 Y multiplexer output
6Y complementary multiplexer output
7OE 3-state output enable input (active LOW)
8 GND ground (0 V)
11, 10, 9 S0,S
1
,S
2select inputs
16 VCC positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.
December 1990 4
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
FUNCTION TABLE
Note
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
Z = high impedance OFF-state
INPUTS OUTPUTS
OE S2S1S0I0I1I2I3I4I5I6I7YY
HXXXXXXXXXXXZZ
L
L
L
L
L
L
L
L
L
L
L
L
L
L
H
H
L
H
X
X
X
X
L
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
H
L
H
L
L
H
L
H
L
L
L
L
L
L
L
L
H
H
H
H
L
L
H
H
X
X
X
X
X
X
X
X
L
H
X
X
X
X
L
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
H
L
H
L
L
H
L
H
L
L
L
L
H
H
H
H
L
L
L
L
L
L
H
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
L
H
X
X
X
X
L
H
X
X
X
X
X
X
X
X
H
L
H
L
L
H
L
H
L
L
L
L
H
H
H
H
H
H
H
H
L
L
H
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
L
H
X
X
X
X
L
H
H
L
H
L
L
H
L
H
Fig.4 Functional diagram. Fig.5 Logic diagram.
December 1990 5
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”
.
Output capability: standard
ICC category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; tr= tf= 6 ns; CL= 50 pF
SYMBOL PARAMETER
Tamb (°C)
UNIT
TEST CONDITIONS
74HC VCC
(V) WAVEFORMS
+25 −40 to +85 −40 to +125
min. typ. max. min. max. min. max.
tPHL/ tPLH propagation delay
Into Y 50
18
14
170
34
29
215
43
37
255
51
43
ns 2.0
4.5
6.0
Fig.6
tPHL/ tPLH propagation delay
Into Y 55
20
16
175
35
30
220
44
37
265
53
45
ns 2.0
4.5
6.0
Fig.7
tPHL/ tPLH propagation delay
Snto Y 66
24
19
205
41
35
255
51
43
310
62
53
ns 2.0
4.5
6.0
Fig.6
tPHL/ tPLH propagation delay
Snto Y 69
25
20
205
41
35
255
51
43
310
62
53
ns 2.0
4.5
6.0
Fig.7
tPZH/ tPZL 3-state output enable time
OE to Y, Y 36
13
10
140
28
24
175
35
30
210
42
36
ns 2.0
4.5
6.0
Fig.7
tPHZ/ tPLZ 3-state output disable time
OE to Y, Y 39
14
11
140
28
24
170
35
30
210
42
36
ns 2.0
4.5
6.0
Fig.7
tTHL/ tTLH output transition time 19
7
6
75
15
13
95
19
16
110
22
19
ns 2.0
4.5
6.0
Figs 6 and 7
December 1990 6
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”
.
Output capability: standard
ICC category: MSI
Note to HCT types
The value of additional quiescent supply current (∆ICC) for a unit load of 1 is given in the family specifications.
To determine ∆ICC per input, multiply this value by the unit load coefficient shown in the table below.
AC CHARACTERISTICS FOR HCT
GND = 0 V; tr= tf= 6 ns; CL= 50 pF
INPUT UNIT LOAD COEFFICIENT
In
S0
S1,S
2
OE
1.00
1.50
1.50
1.50
SYMBOL PARAMETER
Tamb (°C)
UNIT
TEST CONDITIONS
74HCT VCC
(V) WAVEFORMS
+25 −40 to +85 −40 to +125
min. typ. max. min. max. min. max.
tPHL/ tPLH propagation delay
Into Y 22 35 44 53 ns 4.5 Fig.6
tPHL/ tPLH propagation delay
Into Y 22 35 44 53 ns 4.5 Fig.7
tPHL/ tPLH propagation delay
Snto Y 24 44 55 66 ns 4.5 Fig.6
tPHL/ tPLH propagation delay
Snto Y 25 44 55 66 ns 4.5 Fig.7
tPZH/ tPZL 3-state output enable time
OE to Y, Y 13 28 35 42 ns 4.5 Fig.7
tPHZ/ tPLZ 3-state output disable time
OE to Y, Y 14 28 35 42 ns 4.5 Fig.7
tTHL/ tTLH output transition time 7 15 19 22 ns 4.5 Figs 6 and 7
December 1990 7
Philips Semiconductors Product specification
8-input multiplexer; 3-state 74HC/HCT251
AC WAVEFORMS
PACKAGE OUTLINES
See
“74HC/HCT/HCU/HCMOS Logic Package Outlines”
.
Fig.6 Waveforms showing the multiplexer input (In) and select input (Sn) to output (Y) propagation delays and
the output transition times.
(1) HC : VM= 50%; VI= GND to VCC.
HCT: VM= 1.3V; VI= GND to 3 V.
Fig.7 Waveforms showing the multiplexer input (In) and select input (Sn) to output (Y) propagation delays and
the output transition times.
(1) HC : VM= 50%; VI= GND to VCC.
HCT: VM= 1.3V; VI= GND to 3 V.
Fig.8 Waveforms showing the 3-state enable and disable times.
(1) HC : VM= 50%; VI= GND to VCC.
HCT: VM= 1.3V; VI= GND to 3 V.
Philips Semiconductors - PIP - 74HC/HCT251; 8-input multiplexer; 3-state
Philips Semiconductors Home
Product
catalog
Buy
online
MySemiconductors
Contact
Products
•MultiMarket
Semiconductors
•Product Selector
•Catalog by
Function
•Catalog by
System
•Cross-reference
•Packages
•End of Life
information
•Distributors Go
Here!
•Models
•SoC solutions
Product Information
74HC/HCT251; 8-
input multiplexer; 3-
state
Information as of 2003-04-22
My.Semiconductors.COM.
Your personal service from
Philips Semiconductors.
Please register now !
Stay informed
Use right mouse button to
download datasheet
Download datasheet
General description Features Applications Datasheet
Block diagram Buy online Support & tools Email/translate
Products & packages Parametrics Similar products
top
General description
The 74HC/HCT251 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/HCT251 are the logic implementations of single-pole 8-position switches with the state of three select
inputs (S0,S1,S2) controlling the switch positions.
Assertion (Y) and negation (Y) outputs are both provided. The output enable input (OE) is active LOW. The logic function provided at the output, when activated, is:
Y =OE.(I0.S0.S1.S2 + I1.S0.S1.S2 +
+ I2.S0.S1.S2 + I3.S0.S1.S2 +
+ I4.S0.S1.S2 + I5.S0.S1.S2 +
+ I6.S0.S1.S2 + I7.S0.S1.S2)
Both outputs are in the high impedance OFF-state (Z) when the output enable input is HIGH, allowing multiplexer expansion by tying the outputs.
top
Features
● True and complement outputs
● Both outputs are 3-state for further multiplexer expansion
● Multifunction capability
● Permits multiplexing from n-lines to one line
● Output capability: standard
● ICC category: MSI
top
Datasheet
Type number Title Publication
release date Datasheet status Page
count File
size
(kB)
Datasheet
74HC/HCT251 8-input
multiplexer; 3-
state
12/1/1990 Product
specification 7 51
Download
PDF
File
Download
Additional datasheet info
To complete the device datasheet with package and family information, also download the following PDF files. The
file:///G|/imaging/BITTING/CPL/20030424/04232003_9/PHGL/_HTML04232003/74HC251N.html (1 of 4) [Apr-29-2003 1:51:56 PM]
Submit Query
Philips Semiconductors - PIP - 74HC/HCT251; 8-input multiplexer; 3-state
"Logic Package Information" document is required to determine in which package(s) this device is available.
Document Description
1
Download
PDF
File
HCT_FAMILY_SPECIFICATIONS HC/T Family Specifications, The IC06 74HC/HCT/HCMOS Logic
Family Specifications
2
Download
PDF
File
HCT_PACKAGE_INFO HC/T Package Info, The IC06 74HC/HCT/HCMOS Logic Package
Information
3
Download
PDF
File
HCT_PACKAGE_OUTLINES HC/T Package Outlines, The IC06 74HC/HCT/HCMOS Logic
Package Outlines
top
Parametrics
Type number Package Description Propagation
Delay(ns) Voltage No.
of
Pins
Power
Dissipation
Considerations
Logic
Switching
Levels
Output
Drive
Capability
74HC251D SOT109
(SO16)
8-Input
Multiplexer
(3-State) 15 5 Volts
+16 Low Power or
Battery
Applications CMOS Low
74HC251DB SOT338-1
(SSOP16)
8-Input
Multiplexer
(3-State) 15 5 Volts
+16 Low Power or
Battery
Applications CMOS Low
74HC251N SOT38-1
(DIP16)
8-Input
Multiplexer
(3-State) 15 5 Volts
+16 Low Power or
Battery
Applications CMOS Low
74HC251PW SOT403-1
(TSSOP16)
8-Input
Multiplexer
(3-State) 15 5 Volts
+16 Low Power or
Battery
Applications CMOS Low
74HCT251D SOT109
(SO16)
8-Input
Multiplexer
(3-State);
TTL
Enabled
15 5 Volts
+16 Low Power or
Battery
Applications TTL Low
74HCT251DB SOT338-1
(SSOP16)
8-Input
Multiplexer
(3-State);
TTL
Enabled
15 5 Volts
+16 Low Power or
Battery
Applications TTL Low
74HCT251N SOT38-1
(DIP16)
8-Input
Multiplexer
(3-State);
TTL
Enabled
15 5 Volts
+16 Low Power or
Battery
Applications TTL Low
74HCT251PW SOT403-1
(TSSOP16)
8-Input
Multiplexer
(3-State);
TTL
Enabled
15 5 Volts
+16 Low Power or
Battery
Applications TTL Low
file:///G|/imaging/BITTING/CPL/20030424/04232003_9/PHGL/_HTML04232003/74HC251N.html (2 of 4) [Apr-29-2003 1:51:56 PM]
Philips Semiconductors - PIP - 74HC/HCT251; 8-input multiplexer; 3-state
top
Products, packages, availability and ordering
Type number North
American type
number
Ordering code
(12NC) Marking/Packing
Download
PDF
File
Discretes
packing info
Package Device status Buy online
74HC251D 74HC251D 9337 135 20652 Standard Marking
* Bulk Pack,
CECC
SOT109
(SO16) Full production
order this
product
online
-
74HC251D-T 9337 135 20653 Standard Marking
* Reel Pack,
SMD, 13", CECC
SOT109
(SO16) Full production
order this
product
online
-
74HC251DB 74HC251DB 9351 886 50112 Standard Marking
* Bulk Pack SOT338-1
(SSOP16) Full production
order this
product
online
-
74HC251DB-
T 9351 886 50118 Standard Marking
* Reel Pack,
SMD, 13"
SOT338-1
(SSOP16) Full production
order this
product
online
-
74HC251N 74HC251N 9336 695 30652 Standard Marking
* Bulk Pack,
CECC
SOT38-1
(DIP16) Full production
order this
product
online
-
74HC251PW 74HC251PW 9351 883 90112 Standard Marking
* Bulk Pack
SOT403-1
(TSSOP16)
Full production
order this
product
online
-
74HC251PW-
T 9351 883 90118 Standard Marking
* Reel Pack,
SMD, 13"
SOT403-1
(TSSOP16)
Full production
order this
product
online
-
74HCT251D 74HCT251D 9337 135 30652 Standard Marking
* Bulk Pack,
CECC
SOT109
(SO16) Full production
order this
product
online
-
74HCT251D-
T 9337 135 30653 Standard Marking
* Reel Pack,
SMD, 13", CECC
SOT109
(SO16) Full production
order this
product
online
-
74HCT251DB 74HCT251DB 9351 886 40112 Standard Marking
* Bulk Pack SOT338-1
(SSOP16) Full production
order this
product
online
-
74HCT251DB-
T 9351 886 40118 Standard Marking
* Reel Pack,
SMD, 13"
SOT338-1
(SSOP16) Full production
order this
product
online
-
74HCT251N 74HCT251N 9336 701 60652 Standard Marking
* Bulk Pack,
CECC
SOT38-1
(DIP16) Full production
order this
product
online
-
74HCT251PW 74HCT251PW 9351 883 80112 Standard Marking
* Bulk Pack
SOT403-1
(TSSOP16)
Full production
order this
product
online
-
74HCT251PW-
T 9351 883 80118 Standard Marking
* Reel Pack,
SMD, 13"
SOT403-1
(TSSOP16)
Full production
order this
product
online
-
Products in the above table are all in production. Some variants are discontinued; click here for information on these
variants.
file:///G|/imaging/BITTING/CPL/20030424/04232003_9/PHGL/_HTML04232003/74HC251N.html (3 of 4) [Apr-29-2003 1:51:56 PM]
Philips Semiconductors - PIP - 74HC/HCT251; 8-input multiplexer; 3-state
top
Similar products
Products
similar
to
74HC/HCT251
74HC/HCT251 links to the similar products page containing an overview of products that are similar in
function or related to the type number(s) as listed on this page. The similar products page includes products from the
same catalog tree(s), relevant selection guides and products from the same functional category.
top
Support & tools
Download
PDF
File
HC/T Family Specifications, The IC06 74HC/HCT/HCMOS Logic Family Specifications(date 01-Mar-98)
Download
PDF
File
HC/T User Guide(date 01-Nov-97)
top
Email/translate this product information
● Email this product information.
● Translate this product information page from English to:
The English language is the official language used at the semiconductors.philips.com website and webpages. All
translations on this website are created through the use of Google Language Tools and are provided for convenience
purposes only. No rights can be derived from any translation on this website.
About this Web Site
| Copyright © 2003 Koninklijke Philips N.V. All rights reserved. | Privacy Policy |
| Koninklijke Philips N.V. | Access to and use of this Web Site is subject to the following Terms of Use. |
file:///G|/imaging/BITTING/CPL/20030424/04232003_9/PHGL/_HTML04232003/74HC251N.html (4 of 4) [Apr-29-2003 1:51:56 PM]
French
Translate
