ISL3179E Datasheet, PDF (7/17 Pages) Intersil Corporation – High ESD Protected, +125°C, 40Mbps 3.3V, Full Fail-Safe, RS-485/RS-422 Transceivers

ISL3179E, ISL3180E
Test Circuits and Waveforms (Continued)
3V
DI
1.5V
1.5V
0V
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
R_D
C_D
OUT (Z)
OUT (Y)
t_PLH
DIFF OUT (Y - Z)
90%
10%
t_R
t_PHL
90%
10%
t_F
FIGURE 2A. TEST CIRCUIT
SKEW = |t_PLH - t_PHL|
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
110Ω
V_CC
50pF
SW ^GND
OUTPUT
RE
DI
Y/Z
X
1/0
Y/Z
X
0/1
Y/Z
0 (Note 6)
1/0
Y/Z
0 (Note 6)
0/1
Y/Z
1 (Note 9)
1/0
Y/Z
1 (Note 9)
0/1
FIGURE 3A. TEST CIRCUIT
SW
GND
V_CC
GND
V_CC
GND
V_CC
DE
(Note 8)
t_ZH, t_ZH(SHDN)
(Note 8)
OUT (Y, Z)
t_ZL, t_ZL(SHDN)
(Note 8)
OUT (Y, Z)
1.5V
3V
1.5V
0V
t_HZ
OUTPUT HIGH
50%
V_OH - 0.5V ^VOH
0V
t_LZ
50%
OUTPUT LOW
V_CC
V_OL + 0.5V _VOL
FIGURE 3B. MEASUREMENT POINTS
FIGURE 3. DRIVER ENABLE AND DISABLE TIMES
DE
V_CC
DI
SIGNAL
GENERATOR
Z
D
Y
+
C_L
54Ω
V_OD
-
C_L
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
7
FN6365.2
April 22, 2008