TI SN74ALS156N

SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
D
D
D
D OR N PACKAGE
(TOP VIEW)
Applications:
– Dual 2-Line to 4-Line Decoder
– Dual 1-Line to 4-Line Demultiplexer
– 3-Line to 8-Line Decoder
– 1-Line to 8-Line Demultiplexer
Individual Strobes Simplify Cascading for
Decoding or Demultiplexing Larger Words
Package Options Include Plastic
Small-Outline (D) Packages and Standard
Plastic (N) 300-mil DIPs
1C
1G
B
1Y3
1Y2
1Y1
1Y0
GND
1
16
2
15
3
14
4
13
5
12
6
11
7
10
8
9
VCC
2C
2G
A
2Y3
2Y2
2Y1
2Y0
description
One of the main applications of the SN74ALS156 is as a dual 1-line to 4-line decoder /demultiplexer with
individual strobes (G) and common binary-address inputs in a single 16-pin package. When both sections are
enabled, the common binary-address inputs sequentially select and route associated input data to the
appropriate output of each section. The individual strobes permit enabling or disabling each of the 4-bit sections,
as desired.
Data applied to input 1C is inverted at its outputs and data applied at input 2C is not inverted through its outputs.
The inverter following the 1C data input permits use of the SN74ALS156 as a 3-line to 8-line demultiplexer
without external gating. All inputs are clamped with high-performance Schottky diodes to suppress line ringing
and simplify system design.
The SN74ALS156 is characterized for operation from 0°C to 70°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright  1996, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
Function Tables
2-LINE TO 4-LINE DECODER OR
1-LINE TO 4-LINE DEMULTIPLEXER
INPUTS
SELECT
OUTPUTS
B
A
STROBE
1G
DATA
1C
X
X
H
X
1Y0
1Y1
1Y2
1Y3
H
H
H
H
L
L
L
H
L
H
H
H
L
H
L
H
H
L
H
H
H
L
L
H
H
H
L
H
H
H
L
H
H
H
H
L
X
X
X
L
H
H
H
H
2-LINE TO 4-LINE DECODER OR
1-LINE TO 4-LINE DEMULTIPLEXER
INPUTS
SELECT
OUTPUTS
B
A
STROBE
2G
DATA
2C
2Y0
2Y1
2Y2
2Y3
X
X
H
X
H
H
H
H
L
L
L
L
L
H
H
H
L
H
L
L
H
L
H
H
H
L
L
L
H
H
L
H
H
H
L
L
H
H
H
L
X
X
X
H
H
H
H
H
3-LINE TO 8-LINE DECODER OR
1-LINE TO 8-LINE DEMULTIPLEXER
INPUTS
SELECT
OUTPUTS
STROBE
OR
DATA
G‡
0
1
2
3
4
5
6
7
2Y0
2Y1
2Y2
2Y3
1Y0
1Y1
1Y2
1Y3
C†
B
A
X
X
X
H
H
H
H
H
H
H
H
H
L
L
L
L
L
H
H
H
L
H
H
H
L
L
H
L
H
L
H
H
H
L
H
H
L
H
L
L
H
H
L
H
H
H
H
H
L
H
H
L
H
H
H
L
H
H
H
H
H
L
L
L
H
H
H
H
L
H
H
H
H
L
H
L
H
H
H
H
H
L
H
H
H
H
L
L
H
H
L
H
H
H
L
H
H
H
L
H
H
H
L
H
H
H
L
H
† C = inputs 1C and 2C connected together
‡ G = inputs 1G and 2G connected together
2
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
logic symbols† (alternatives)
1-LINE TO 4-LINE DEMULTIPLEXER
2-LINE TO 4-LINE DECODER
X/Y
0 α
2
1G
1C
A
B
A
7
&
EN
1
13
9
10
1 β
&
2G
4
0 β
2
14
5
2 α
3 α
1
3
6
1 α
11
2 β
15
EN
2C
12
3 β
1Y0
B
13
0
3
G
1
1Y1
DMUX 0
1Y2
1Y3
2Y0
0
3
2
1G
1C
1
G4
1
4
2
3
2Y1
15
11
2G
12
B
0
2
1
2
C
15
3
4
4
5
2
G
14
6
EN
1Y1
1Y2
1Y3
2Y0
2Y1
2Y2
2Y3
DMUX
1
1
1Y0
1-LINE TO 8-LINE DEMULTIPLEXER
X/Y
3
4
10
3-LINE TO 8-LINE DECODER
A
5
14
2C
13
6
9
2Y2
2Y3
7
7
9
10
11
12
7
6
5
4
2Y0
2Y1
A
B
13
3
G
2Y2
2Y3
C
1Y0
1
15
1Y3
0
7
1
2
3
2
4
5
1Y1
1Y2
0
0
2
G
14
6
7
9
10
11
12
7
6
5
4
2Y0
2Y1
2Y2
2Y3
1Y0
1Y1
1Y2
1Y3
† These symbols are in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
logic diagram (positive logic)
7
Strobe 1G
Data 1C
2
6
1
5
B
1Y0
1Y1
1Y2
3
4
1Y3
Select
9
A
13
10
Data 2C
Strobe 2G
11
15
2Y0
2Y1
2Y2
14
12
2Y3
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
recommended operating conditions
MIN
NOM
MAX
4.5
5
5.5
UNIT
VCC
VIH
Supply voltage
VIL
VOH
Low-level input voltage
0.8
V
High-level output voltage
5.5
V
IOL
TA
Low-level output current
4
High-level input voltage
2
Operating free-air temperature
0
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
V
V
8
mA
70
°C
SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VIK
VCC = 4.5 V,
VOL
VCC = 4
4.5
5V
IOH
II
VCC = 4.5 V,
VCC = 5.5 V,
IIH
IIL
VCC = 5.5 V,
VCC = 5.5 V,
TYP†
MIN
II = – 18 mA
IOL = 4 mA
IOL = 8 mA
VOH = 5.5 V
MAX
UNIT
– 1.5
V
0.25
0.4
0.35
0.5
V
0.1
mA
VI = 7 V
VI = 2.7 V
0.1
mA
20
µA
VI = 0.4 V
– 0.1
µA
9
mA
ICCL
VCC = 5.5 V
† All typical values are at VCC = 5 V, TA = 25°C.
5
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A B
A,
1Y 2Y
1Y,
tPLH
tPHL
1C
1Y
tPLH
tPHL
1G
1Y
tPLH
tPHL
2C 2G
2C,
2Y
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500 Ω,
TA = MIN to MAX‡
MIN
MAX
7
55
6
25
7
50
6
23
7
38
6
22
7
38
6
22
UNIT
ns
ns
ns
ns
‡ For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
5
SN74ALS156
DECODER/DEMULTIPLEXER
WITH OPEN-COLLECTOR OUTPUTS
SDAS099C – JUNE 1986 – REVISED MAY 1996
PARAMETER MEASUREMENT INFORMATION
SERIES 54ALS/74ALS AND 54AS/74AS DEVICES
7V
RL = R1 = R2
VCC
S1
RL
R1
Test
Point
From Output
Under Test
CL
(see Note A)
From Output
Under Test
RL
Test
Point
From Output
Under Test
CL
(see Note A)
CL
(see Note A)
LOAD CIRCUIT FOR
BI-STATE
TOTEM-POLE OUTPUTS
LOAD CIRCUIT
FOR OPEN-COLLECTOR OUTPUTS
3.5 V
Timing
Input
Test
Point
LOAD CIRCUIT
FOR 3-STATE OUTPUTS
3.5 V
High-Level
Pulse
1.3 V
R2
1.3 V
1.3 V
0.3 V
0.3 V
tsu
Data
Input
tw
th
3.5 V
1.3 V
3.5 V
Low-Level
Pulse
1.3 V
0.3 V
1.3 V
0.3 V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
VOLTAGE WAVEFORMS
PULSE DURATIONS
3.5 V
Output
Control
(low-level
enabling)
1.3 V
1.3 V
0.3 V
tPZL
Waveform 1
S1 Closed
(see Note B)
tPLZ
[3.5 V
3.5 V
tPHZ
VOL
0.3 V
0.3 V
[0 V
1.3 V
0.3 V
tPHL
tPLH
VOH
In-Phase
Output
1.3 V
1.3 V
VOL
tPLH
tPHL
VOH
1.3 V
1.3 V
Input
1.3 V
tPZH
Waveform 2
S1 Open
(see Note B)
1.3 V
VOH
Out-of-Phase
Output
(see Note C)
1.3 V
1.3 V
VOL
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES, 3-STATE OUTPUTS
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. When measuring propagation delay items of 3-state outputs, switch S1 is open.
D. All input pulses have the following characteristics: PRR ≤ 1 MHz, tr = tf = 2 ns, duty cycle = 50%.
E. The outputs are measured one at a time with one transition per measurement.
Figure 1. Load Circuits and Voltage Waveforms
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
IMPORTANT NOTICE
Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue
any product or service without notice, and advise customers to obtain the latest version of relevant information
to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those
pertaining to warranty, patent infringement, and limitation of liability.
TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed, except those mandated by government requirements.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF
DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL
APPLICATIONS”). TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, AUTHORIZED, OR
WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT DEVICES OR SYSTEMS OR OTHER
CRITICAL APPLICATIONS. INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO
BE FULLY AT THE CUSTOMER’S RISK.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent
that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other
intellectual property right of TI covering or relating to any combination, machine, or process in which such
semiconductor products or services might be or are used. TI’s publication of information regarding any third
party’s products or services does not constitute TI’s approval, warranty or endorsement thereof.
Copyright  1998, Texas Instruments Incorporated