ISL3170E_08 Datasheet, PDF (9/19 Pages) Intersil Corporation – RS-485/RS-422 Transceivers

ISL3170E, ISL3171E, ISL3172E, ISL3173E, ISL3174E, ISL3175E, ISL3176E, ISL3177E, ISL3178E
Test Circuits and Waveforms (Continued)
FIGURE 1. DC DRIVER TEST CIRCUITS
3V
DI
1.5V
1.5V
0V
DE
V_CC
DI
Z
D
Y
R_DIFF
C_D
OUT (Z)
OUT (Y)
t_PLH
t_PHL
SIGNAL
GENERATOR
DIFF OUT (Y to Z)
90%
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_OH
V_OL
+V_OD
-V_OD
SIGNAL
GENERATOR
PARAMETER
t_HZ
t_LZ
t_ZH
t_ZL
t_ZH(SHDN)
t_ZL(SHDN)
DE
DI
Z
D
Y
500Ω
V_CC
50pF
SW ^GND
OUTPUT
RE
DI
Y/Z
X
1/0
Y/Z
X
0/1
Y/Z
0 (Note 7)
1/0
Y/Z
0 (Note 7)
0/1
Y/Z
1 (Note 10) 1/0
Y/Z
1 (Note 10) 0/1
SW
GND
V_CC
GND
V_CC
GND
V_CC
DE
NOTE 9
t_ZH, t_ZH(SHDN)
NOTE 9
OUT (Y, Z)
t_ZL, t_ZL(SHDN)
NOTE 9
OUT (Y, Z)
1.5V
3V
1.5V
0V
t_HZ
OUTPUT HIGH
50%
V_OH - 0.25V ^VOH
0V
t_LZ
50%
OUTPUT LOW
V_CC
V_OL + 0.25V _VOL
FIGURE 3A. TEST CIRCUIT
FIGURE 3B. MEASUREMENT POINTS
FIGURE 3. DRIVER ENABLE AND DISABLE TIMES (EXCEPT ISL3171E, ISL3174E, ISL3177E)
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
54Ω
C_D
+
V_OD
-
DI
DIFF OUT (Y to Z)
-V_OD
3V
0V
+V_OD
0V
FIGURE 4A. TEST CIRCUIT
FIGURE 4B. MEASUREMENT POINTS
FIGURE 4. DRIVER DATA RATE
9
FN6307.4
June 10, 2008