SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
•
Package Options Include Plastic
Small-Outline (D) Packages, Ceramic Chip
Carriers (FK), and Standard Plastic (N) and
Ceramic (J) 300-mil DIPs
SN54ALS20A, SN54AS20 . . . J PACKAGE
SN74ALS20A, SN74AS20 . . . D OR N PACKAGE
(TOP VIEW)
description
These devices contain two independent 4-input
positive-NAND gates. They perform the Boolean
functions Y = A
•
B
•
C
•
D or Y = A + B + C + D
in positive logic.
The SN54ALS20A and SN54AS20 are
characterized for operation over the full military
temperature range of – 55°C to 125°C. The
SN74ALS20A and SN74AS20 are characterized
for operation from 0°C to 70°C.
FUNCTION TABLE
(each gate)
INPUTS
A
H
L
X
X
X
B
H
X
L
X
X
C
H
X
X
L
X
D
H
X
X
X
L
OUTPUT
Y
L
H
H
H
H
1A
1B
NC
1C
1D
1Y
GND
1
2
3
4
5
6
7
14
13
12
11
10
9
8
V
CC
2D
2C
NC
2B
2A
2Y
SN54ALS20A, SN54AS20 . . . FK PACKAGE
(TOP VIEW)
1B
1A
NC
V
CC
NC
NC
1C
NC
1D
4
5
6
7
8
3 2 1 20 19
18
17
16
15
14
9 10 11 12 13
2D
2C
NC
NC
NC
2B
6
NC – No internal connection
logic symbol
†
1A
1B
1C
1D
2A
2B
2C
2D
1
2
4
5
9
10
12
13
6
1Y
&
logic diagram (positive logic)
1A
1B
1C
1D
2A
8
2Y
2B
2C
2D
1
2
4
5
9
10
12
13
8
1Y
1Y
GND
NC
2Y
2A
2Y
† This symbol is in accordance with ANSI/IEEE Std 91-1984 and
IEC Publication 617-12.
Pin numbers shown are for the D, J, and N packages.
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.
Copyright
©
1994, Texas Instruments Incorporated
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
1
SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
†
Supply voltage, V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, V
I
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Operating free-air temperature range, T
A
: SN54ALS20A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 55°C to 125°C
SN74ALS20A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 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
SN54ALS20A
MIN
VCC
VIH
VIL
IOH
IOL
Supply voltage
High-level input voltage
Low-level
Low level input voltage
High-level output current
Low-level output current
– 55
4.5
2
0.8‡
0.7§
– 0.4
4
125
0
NOM
5
MAX
5.5
SN74ALS20A
MIN
4.5
2
0.8
– 0.4
8
70
NOM
5
MAX
5.5
UNIT
V
V
V
mA
mA
°C
TA
Operating free-air temperature
‡ Applies over temperature range – 55°C to 70°C
§ Applies over temperature range 70°C to 125°C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VOH
VOL
II
IIH
IIL
IO#
ICCH
ICCL
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
VCC = 4 5 V
4.5
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
II = –18 mA
IOH = – 0.4 mA
IOL = 4 mA
IOL = 8 mA
VI = 7 V
VI = 2.7 V
VI = 0.4 V
VO = 2.25 V
VI = 0
VI = 4.5 V
– 20
0.22
0.81
SN54ALS20A
MIN TYP¶
MAX
–1.5
VCC – 2
0.25
0.4
0.1
20
– 0.1
– 112
0.4
1.5
– 30
0.22
0.81
VCC – 2
0.25
0.35
0.4
0.5
0.1
20
– 0.1
– 112
0.4
1.5
SN74ALS20A
MIN TYP¶
MAX
–1.5
UNIT
V
V
V
mA
µA
mA
mA
mA
mA
¶ All typical values are at VCC = 5 V, TA = 25°C.
# The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
2
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
switching characteristics (see Figure 1)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500
Ω,
TA = MIN to MAX†
SN54ALS20A
MIN
tPLH
tPHL
A, B, C,
A B C or D
Y
1
1
MAX
12.5
11
SN74ALS20A
MIN
3
3
MAX
11
10
ns
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
UNIT
† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
‡
Supply voltage, V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage, V
I
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Operating free-air temperature range, T
A
: SN54AS20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 55°C to 125°C
SN74AS20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 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
SN54AS20
MIN
VCC
VIH
VIL
IOH
IOL
TA
Supply voltage
High-level input voltage
Low-level input voltage
High-level output current
Low-level output current
Operating free-air temperature
– 55
4.5
2
0.8
–2
20
125
0
NOM
5
MAX
5.5
SN74AS20
MIN
4.5
2
0.8
–2
20
70
NOM
5
MAX
5.5
UNIT
V
V
V
mA
mA
°C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VOH
VOL
II
IIH
IIL
IO¶
ICCH
ICCL
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
VCC = 4.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
VCC = 5.5 V,
II = –18 mA
IOH = – 2 mA
IOL = 20 mA
VI = 7 V
VI = 2.7 V
VI = 0.4 V
VO = 2.25 V
VI = 0
– 30
1
SN54AS20
MIN TYP§
MAX
–1.2
VCC – 2
0.35
0.5
0.1
20
– 0.5
– 112
1.6
– 30
1
VCC – 2
0.35
0.5
0.1
20
– 0.5
– 112
1.6
SN74AS20
MIN TYP§
MAX
–1.2
UNIT
V
V
V
mA
µA
mA
mA
mA
VCC = 5.5 V,
VI = 4.5 V
5.4
8.7
5.4
8.7
mA
§ All typical values are at VCC = 5 V, TA = 25°C.
¶ The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
3
SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
switching characteristics (see Figure 1)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500
Ω,
TA = MIN to MAX†
SN54AS20
MIN
tPLH
tPHL
A, B, C,
A B C or D
Y
1
1
MAX
5.5
5
SN74AS20
MIN
1
1
MAX
5
4.5
ns
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
UNIT
† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.
4
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
PARAMETER MEASUREMENT INFORMATION
SERIES 54ALS/74ALS AND 54AS/74AS DEVICES
7V
VCC
S1
RL
From Output
Under Test
CL
(see Note A)
RL
Test
Point
R1
From Output
Under Test
CL
(see Note A)
Test
Point
From Output
Under Test
CL
(see Note A)
R2
Test
Point
RL = R1 = R2
LOAD CIRCUIT FOR
BI-STATE
TOTEM-POLE OUTPUTS
LOAD CIRCUIT
FOR OPEN-COLLECTOR OUTPUTS
LOAD CIRCUIT
FOR 3-STATE OUTPUTS
Timing
Input
tsu
Data
Input
1.3 V
3.5 V
1.3 V
0.3 V
th
3.5 V
1.3 V
0.3 V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
High-Level
Pulse
3.5 V
1.3 V
tw
1.3 V
0.3 V
Low-Level
Pulse
3.5 V
1.3 V
1.3 V
0.3 V
VOLTAGE WAVEFORMS
PULSE DURATIONS
Output
Control
(low-level
enabling)
tPZL
Waveform 1
S1 Closed
(see Note B)
3.5 V
1.3 V
1.3 V
0.3 V
tPLZ
1.3 V
VOL
0.3 V
VOH
1.3 V
0.3 V
3.5 V
Input
tPLH
In-Phase
Output
1.3 V
1.3 V
1.3 V
0.3 V
tPHL
VOH
1.3 V
VOL
tPLH
VOH
1.3 V
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
1.3 V
VOL
[
3.5 V
tPHZ
tPZH
Waveform 2
S1 Open
(see Note B)
tPHL
Out-of-Phase
Output
(see Note C)
[
0 V
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
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
5
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