DS8921 Datasheet, PDF (3/8 Pages) National Semiconductor (TI) – Differential Line Driver and Receiver Pair

Receiver Switching Characteristics
Figure 1(Figure 2)
Symbol
Conditions
Min
Typ
T_pLH
C_L = 30 pF
14
(Figures 1, 2 )
T_pHL
C_L = 30 pF
14
(Figures 1, 2)
|T_pLH–T _pHL|
C_L = 30 pF
0.5
(Figures 1, 2 )
8921
22.5
22.5
5
Max
8921A
20
20
3.5
8921AT
20
20
5
Units
ns
ns
ns
Driver Switching Characteristics
SINGLE ENDED CHARACTERISTICS (Figures 3, 4)
Symbol
Conditions
Min
Typ
T_pLH
C_L = 30 pF
10
(Figures 3, 4)
T_pHL
C_L = 30 pF
10
(Figures 3, 4)
T_TLH
C_L = 30 pF
5
(Figures 7, 8)
T_THL
C_L = 30 pF
5
(Figures 7, 8)
Skew
CL = 30 pF
1
(Figures 3, 4)
8921
15
15
8
8
5
Max
8921A
15
15
8
8
3.5
8921AT
15
15
9.5
9.5
3.5
Units
ns
ns
ns
ns
ns
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)
Min
Typ
Max
Units
8921
8921A
8921AT
10
15
15
15
ns
10
15
15
15
ns
0.5
6
2.75
2.75
ns
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:
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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