ISL31470E_10 Datasheet, PDF (10/21 Pages) Intersil Corporation – Fault Protected, Extended Common Mode Range, RS-485/RS-422 Transceivers

ISL31470E, ISL31472E, ISL31475E, ISL31478E
Test Circuits and Waveforms (Continued)
3V
DI
1.5V
1.5V
0V
OUT (Z)
t_PLH
t_PHL
V_OH
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
C_D
R_D
OUT (Y)
90%
DIFF OUT (Y - Z)
10%
t_R
90%
10%
t_F
SKEW = |t_PLH - t_PHL|
FIGURE 2A. TEST CIRCUIT
FIGURE 2B. MEASUREMENT POINTS
FIGURE 2. DRIVER PROPAGATION DELAY AND DIFFERENTIAL TRANSITION TIMES
V_OL
+V_OD
-V_OD
SIGNAL
GENERATOR
DE
Z
DI
D
Y
110Ω
SW
C_L
V_CC
GND
PARAMETER OUTPUT
RE
DI
t_HZ
t_LZ
t_ZH
t_ZL
t_ZH(SHDN)
t_ZL(SHDN)
Y/Z
X
1/0
Y/Z
X
0/1
Y/Z 0 (Note 11) 1/0
Y/Z 0 (Note 11) 0/1
Y/Z 1 (Note 14) 1/0
Y/Z 1 (Note 14) 0/1
SW
GND
V_CC
GND
V_CC
GND
V_CC
C_L
(pF)
50
50
100
100
100
100
DE
Note 13
t_ZH, t_ZH(SHDN)
Note 13
OUT (Y, Z)
t_ZL, t_ZL(SHDN)
Note 13
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
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
54Ω
C_D
+
V_OD
-
DI
DIFF OUT (Y - Z)
-V_OD
3V
0V
+V_OD
0V
FIGURE 4A. TEST CIRCUIT
FIGURE 4B. MEASUREMENT POINTS
FIGURE 4. DRIVER DATA RATE
10
FN7639.0
June 17, 2010