ISL4485E Datasheet, PDF (5/11 Pages) Intersil Corporation – ±15kV ESD Protected, 20Mbps, 5V, Low Power, RS-485/RS-422 Transceiver

ISL4485E
Test Circuits and Waveforms (Continued)
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
500Ω
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
15
0/1
V_CC
15
1/0 GND 100
0/1
V_CC
100
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
5