Datasheet

   
  
  
SDLS213B − DECEMBER 1983 − REVISED NOVEMBER 2004
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
switching characteristics V
CC
= 5 V, R
L
= 400 Ω, T
A
= 25_C (see Figures 1 and 2)
PARAMETER
FROM
TO
TEST CONDITIONS
SN54221 SN74221
UNIT
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
TEST CONDITIONS
MIN TYP MAX MIN TYP MAX
UNIT
t
PLH
A
Q
45 70 45 70
t
PLH
B
Q
C
ext
= 80 pF,
R
ext
= 2 kΩ
35 55 35 55
ns
t
PHL
A
Q
C
ext
= 80 pF,
R
ext
= 2 k
Ω
50 80 50 80
ns
t
PHL
B
Q
40 65 40 65
t
PHL
CLR
Q
C
ext
= 80 pF,
R
ext
= 2 kΩ
27 27
ns
t
PLH
CLR
Q
C
ext
= 80 pF,
R
ext
= 2 k
Ω
40 40
ns
C
ext
= 80 pF, R
ext
= 2 kΩ
70 110 150 70 110 150
t
w
A or B
Q or Q
C
ext
= 0, R
ext
= 2 kΩ
17 30 50 17 30 50
ns
t
w
A or B
Q or Q
C
ext
= 100 pF, R
ext
= 10 kΩ
650 700 750 650 700 750
ns
C
ext
= 1 µF, R
ext
= 10 kΩ
6.5* 7 7.5* 6.5 7 7.5 ms
∗ On products compliant to MIL-PRF-38535, this parameter is not production tested.
recommended operating conditions (see Note 4)
SN54LS221 SN74LS221
UNIT
MIN NOM MAX MIN NOM MAX
UNIT
V
CC
Supply voltage 4.5 5 5.5 4.75 5 5.25 V
I
OH
High-level output current −400 −400 µA
I
OL
Low-level output current 4 8 mA
∆v/∆t
Rise or fall of input pulse rate
B input 1
*
1 V/s
∆v/∆t Rise or fall of input pulse rate
A input
1
*
1 V/µs
T
A
Operating free-air temperature −55 125 0 70 °C
∗ On products compliant to MIL-PRF-38535, this parameter is not production tested.
NOTE 4: All unused inputs of the device must be held at V
CC
or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.