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SN54ALS20A, SN54AS20, SN74ALS20A, SN74AS20
DUAL 4-INPUT POSITIVE-NAND GATES
SDAS192B – APRIL 1982 – REVISED DECEMBER 1994
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
switching characteristics (see Figure 1)
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
RL = 500
,
TA = MIN to MAX
SN54ALS20A
MIN
MAX
1
12.5
1
11
UNIT
SN74ALS20A
MIN
3
3
MAX
tPLH
tPHL
A B C or D
A, B, C, or D
Y
11
10
ns
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
Input voltage, V
I
Operating free-air temperature range, T
A
: SN54AS20
7 V
7 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SN74AS20
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
–55
°
C to 125
°
C
0
°
C to 70
°
C
–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
NOM
SN74AS20
MIN
NOM
UNIT
MAX
MAX
VCC
VIH
VIL
IOH
IOL
TA
Supply voltage
4.5
5
5.5
4.5
5
5.5
V
High-level input voltage
2
2
V
Low-level input voltage
0.8
0.8
V
High-level output current
–2
–2
mA
Low-level output current
20
20
mA
°
C
Operating free-air temperature
–55
125
0
70
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
SN54AS20
MIN
TYP§
SN74AS20
MIN
TYP§
UNIT
MAX
MAX
VIK
VOH
VOL
II
IIH
IIL
IO
ICCH
ICCL
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,
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
VI = 4.5 V
–1.2
–1.2
V
VCC –2
VCC –2
V
0.35
0.5
0.35
0.5
V
0.1
0.1
mA
μ
A
mA
20
20
–0.5
–0.5
–30
–112
–30
–112
mA
1
1.6
1
1.6
mA
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.