ISL4486 Datasheet, PDF (5/11 Pages) Intersil Corporation – 5V, Ultra High Speed, PROFIBUS, RS-485/RS-422 Transceivers

Test Circuits and Waveforms
ISL4486, ISL81486
V_CC ^DE
DI
Z
D
Y
V_OD
R
R
V_OC
V_CC ^DE
DI
Z
D
Y
V_OD
375Ω
R_D = 60Ω
V_CM
-7V to +12V
375Ω
FIGURE 1A. V_OD AND V_OC
FIGURE 1B. V_OD WITH COMMON MODE LOAD
FIGURE 1. DC DRIVER TEST CIRCUITS
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
C_L = 100pF
R_DIFF
C_L = 100pF
DI
OUT (Y)
OUT (Z)
1.5V
t_PLH
50%
t_PHL
50%
3V
1.5V
0V
t_PHL
50%
V_OH
V_OL
t_PLH
50%
V_OH
V_OL
DIFF OUT (Y - Z)
90%
10%
t_R
90%
10%
t_F
+V_OD
-V_OD
SKEW = |CROSSING PT. OF Y↑ & Z↓ - CROSSING PT. OF Y↓ & Z↑|
FIGURE 2A. TEST CIRCUIT
FIGURE 2B. MEASUREMENT POINTS
FIGURE 2. DRIVER PROPAGATION DELAY AND DIFFERENTIAL TRANSITION TIMES
DE
DI
SIGNAL
GENERATOR
Z
D
Y
C_L
110Ω
V_CC
SW ^GND
PARAMETER OUTPUT RE
t_HZ
Y/Z
X
t_LZ
Y/Z
X
t_ZH
Y/Z
X
t_ZL
Y/Z
X
DI
SW C_L (pF)
1/0 GND
50
0/1
V_CC
50
1/0 GND
50
0/1
V_CC
50
DE
t_ZH
OUT (Y, Z)
t_ZL
OUT (Y, Z)
1.5V
3V
1.5V
0V
t_HZ
OUTPUT HIGH
2.3V
V_OH - 0.5V ^VOH
0V
t_LZ
2.3V
OUTPUT LOW
V_CC
V_OL + 0.5V _VOL
FIGURE 3A. TEST CIRCUIT
FIGURE 3B. MEASUREMENT POINTS
FIGURE 3. DRIVER ENABLE AND DISABLE TIMES
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