Datasheet

MAX3157
High CMRR RS-485 Transceiver
with ±50V Isolation
_______________________________________________________________________________________ 7
DE
5V/div
VY
10V/div
100µs/div
0
+50V
POWER-UP DELAY
(V
ISOCOM
= +50V)
MAX3157toc19
0
20
10
40
30
50
60
0.1 1 10
MAXIMUM COMMON-MODE PEAK VOLTAGE TO
GROUND vs. COMMON-MODE FREQUENCY
MAX3157 toc20
COMMON-MODE FREQUENCY (kHz)
COMMON-MODE PEAK VOLTAGE TO GROUND (V)
MAXIMUM COMMON PEAK
VOLTAGE TO ISOCOM
COMMON-MODE VOLTAGE TO
ISOCOM = 7V PEAK
Typical Operating Characteristics (continued)
(V
CC
= +5V, YR = ZR = AR = BR = ISOCOM, C1 = C2 = 0.047µF, C3 = 1µF, C4 = 10nF, T
A
= +25°C, unless otherwise noted.)
Test Circuits and Timing Diagrams
R
R
Y
Z
V
OD
V
OC
Figure 1. Driver DC Test Load
DI
DE
3V
Y
Z
C
L1
C
L2
R
DIFF
V
ID
Figure 3. Driver Timing Test Circuit
RECEIVER
OUTPUT
TEST POINT
1kΩ
1kΩ
S1
S2
V
CC
C
L
100pF
OUTPUT
UNDER TEST
500Ω
S1
S2
V
CC
C
L
Figure 2. Receiver Enable/Disable Timing Test Load
Figure 4. Driver Enable/Disable Timing Test Load