Receiver Switching Characteristics
Figure 1(Figure 2)
Symbol
T
pLH
T
pHL
|T
pLH
–T
pHL
|
Conditions
C
L
= 30 pF
(Figures
1, 2
)
C
L
= 30 pF
(Figures
1, 2)
C
L
= 30 pF
(Figures
1, 2
)
Min
Typ
8921
14
14
0.5
22.5
22.5
5
Max
8921A
20
20
3.5
8921AT
20
20
5
ns
ns
ns
Units
Driver Switching Characteristics
SINGLE ENDED CHARACTERISTICS
(Figures
3, 4)
Symbol
T
pLH
T
pHL
T
TLH
T
THL
Skew
Conditions
C
L
= 30 pF
(Figures
3, 4)
C
L
= 30 pF
(Figures
3, 4)
C
L
= 30 pF
(Figures
7, 8)
C
L
= 30 pF
(Figures
7, 8)
CL = 30 pF
(Figures
3, 4)
Min
Typ
8921
10
10
5
5
1
15
15
8
8
5
Max
8921A
15
15
8
8
3.5
8921AT
15
15
9.5
9.5
3.5
ns
ns
ns
ns
ns
Units
Driver Switching Characteristics
(Note 6)
DIFFERENTIAL CHARACTERISTICS
(Figures
3, 5)
Symbol
T
pLH
T
pHL
|T
pLH
–T
pHL
|
Conditions
C
L
= 30 pF
(Figures
3, 5, 6)
C
L
= 30 pF
(Figures
3, 5, 6)
C
L
= 30 pF
(Figures
3, 5, 6)
Note 1:
“Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device
should be operated at these limits. The Table of “Electrical Characteristics” provides conditions for actual device operation.
Note 2:
All currents into device pins are shown as positive values; all currents out of the device are shown as negative; all voltages are referenced to ground unless
otherwise specified. All values shown as max or min are classified on absolute value basis.
Note 3:
All typical values are V
CC
= 5V, T
A
= 25˚C.
Note 4:
Only one output at a time should be shorted.
Note 5:
Difference between complementary outputs at the 50% point.
Note 6:
Differential Delays are defined as calculated results from single ended rise and fall time measurements. This approach in establishing AC performance speci-
fications has been taken due to limitations of available Automatic Test Equipment (ATE).
The calculated ATE results assume a linear transition between measurement points and are a result of the following equations:
Min
Typ
8921
10
10
0.5
15
15
6
Max
8921A
15
15
2.75
8921AT
15
15
2.75
Units
ns
ns
ns
Where: T
cr
= Crossing Point
T
ra
, T
rb
, T
fa
and T
fb
are time measurements with respect to the input. See
Figure 6
.
3
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