Datasheet

MAX3480EA/MAX3480EB
±15kV ESD-Protected, Isolated, 3.3V
RS-485/RS-422 Data Interfaces
______________________________________________________________________________________ 11
_________________________________________________________________Test Circuits
Figure 3. Driver DC Test Load Figure 4. Driver/Receiver Timing Test Circuit
Figure 5. Driver Timing Test Load
R
R
A
B
V
OD
V
OC
DI
´
DE
´
+3.3V
A
B
C
L1
C
L2
A
B
RO
R3
+3.3V
R
DIFF
V
ID
ISOLATION BARRIER ISOLATION BARRIER
RD
OUTPUT
UNDER TEST
500Ω
S1
S2
ISO V
CC1,
ISO V
CC2
C
L
_______________________________________________________Switching Waveforms
Figure 6. Driver Propagation Delays and Transition Times Figure 7. Driver Enable and Disable Times
DI
´
V
CC
_ - 0.4V
V
CC
_ - 0.4V
2
V
CC
_ - 0.4V
2
0
B
A
V
O
0
-V
O
V
O
t
PLH
1/2 V
O
10%
t
R
90%
90%
t
PHL
1/2 V
O
10%
t
F
V
DIFF
= V
A
- V
B
V
DIFF
t
SKEW = |
t
PLH
- t
PHL |
OUTPUT NORMALLY LOW
OUTPUT NORMALLY HIGH
0
A, B
V
OL
A, B
0
V
OL
+ 0.5V
V
OH
- 0.5V
2.3V
2.3V
t
ZL
t
LZ
t
ZH
t
HZ
DE
´
V
CC
_ - 0.4V
V
CC
_ - 0.4V
2
V
CC
_ - 0.4V
2