DS8925 Datasheet, PDF (4/16 Pages) National Semiconductor (TI) – LocalTalk™ Dual Driver/Triple Receiver

Switching Characteristics (Notes 4, 5)
Over Supply Voltage and Operating Temperature Ranges, unless otherwise specified
Symbol
Parameter
Conditions
Min Typ Max Units
DIFFERENTIAL DRIVER CHARACTERISTICS
t_PHLD
Differential Propagation Delay High to Low
t_PLHD
Differential Propagation Delay Low to High
t_SKD
Differential Skew |t_PHLD − t_PLHD|
t_r
Rise Time
t_f
Fall Time
t_PHZ
Disable Time High to Z
t_PLZ
Disable Time Low to Z
t_PZH
Enable Time Z to High
t_PZL
Enable Time Z to Low
SINGLE ENDED DRIVER CHARACTERISTICS
t_PHL
Propagation Delay High to Low
t_PLH
Propagation Delay Low to High
t_SK
Skew, |t_PHL − t_PLH
t_r
Rise Time
t_f
Fall Time
RECEIVER CHARACTERISTICS
t_PHL
Propagation Delay High to Low
t_PLH
Propagation Delay Low to High
t_SK
Skew, |t_PHL − t_PLH|
R_L = 100Ω, C_L = 500 pF,
70 134 350
ns
(Figures 3, 4)
70 141 350
ns
C₁ = C₂ = 50 pF
7
50
ns
50 140 300
ns
50 140 300
ns
R_L = 100Ω, C_L = 500 pF
(Figures 7, 8)
300 600
ns
300 600
ns
160 350
ns
160 350
ns
R_L = 450Ω, C_L = 500 pF
(Figures 5, 6)
70 120 350
ns
70 150 350
ns
30
70
ns
50 100 300
ns
20
50 300
ns
C_L = 15 pF
(Figures 9, 10)
10
33
75
ns
10
30
75
ns
3
20
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 devices
should be operated at these limits. The table of Electrical Characteristics specifies conditions of device operation.
Note 2: Current into device pins is defined as positive. Current out of device pins is defined as negative. All voltages are referenced to ground except V_OD, V_OD1,
V_OD2, and V_SS.
Note 3: All typicals are given for: V_CC = +5.0V, V_EE = −5.0V, T_A = +25˚C unless otherwise specified.
Truth Tables
Driver (D1)
Inputs
D_EN1
H
D_IN1
X
L
L
L
H
Outputs
D_OUT1+
Z
D_OUT1−
Z
L
H
H
L
Driver (D2)
Input
D_IN2
L
H
H = Logic High Level (Steady State)
L = Logic Low Level (Steady State)
X = Irrelevant (Any Input)
Z = Off State (TRI-STATE, High Impedance)
†_{OPEN = Non-Terminated}
Output
D_OUT2−
H
L
Receiver (1)
Input
R_IN1−
≤−200 mV
≥+200 mV
OPEN^†
Receiver (2)
Inputs
R_IN2+ − R_IN2−
≤−200 mV
≥+200 mV
OPEN^†
Receiver (3)
Input
R_IN3+
≤−200 mV
≥+200 mV
OPEN^†
Output
R_OUT1
H
L
H
Output
R_OUT2
L
H
H
Output
R_OUT3
L
H
H
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