MAX1480E Datasheet, PDF (14/19 Pages) Maxim Integrated Products – 15kV ESD-Protected, Isolated RS-485/RS-422

±15kV ESD-Protected, Isolated RS-485/RS-422
Data Interfaces
cuits over the entire common-mode range (see Typical
Operating Characteristics). In addition, a thermal shut-
down circuit forces the driver outputs into a high-im
pedance state if the die temperature rises excessively.
Propagation Delay Skew
Propagation delay skew is the difference between the
low-to-high and high-to-low propagation delay. Small
driver/receiver skew times help reduce EMI and reflec-
tions by maintaining balanced differential signals.
_____________________Function Tables
Half-Duplex Devices
(MAX1480EA/MAX1480EC)
Table 3. Transmitting
INPUTS*
DE´
DI´
1
1
OUTPUTS
B
A
0
1
1
0
1
0
0
X
High-Z
High-Z
X = Don’t care; High-Z = High impedance
10dB/div
0
5MHz
500kHz/div
Figure 11. Driver Output Waveform and FFT Plot of
MAX1480EA/MAX1490EA Transmitting a 150kHz Signal
10dB/div
Table 4. Receiving
INPUTS*
DE´
V_A - V_B
0
≥ +0.2V
0
≤ -0.2V
0
Open
OUTPUT
(RO)
0
1
0
Full-Duplex Devices
(MAX1490EA/MAX1490EB)
Table 5. Transmitting
INPUT*
(DI´)
1
0
OUTPUTS
Z
Y
0
1
1
0
* For DE´ and DI´ pin descriptions, see Detailed Block Diagram
and Typical Application Circuit (Figure 1 for MAX1480EA/
MAX1480EC, Figure 2 for MAX1490EA/MAX1490EB).
0
5MHz
500kHz/div
Figure 12. Driver Output Waveform and FFT Plot of
MAX1480EC/ MAX1490EB Transmitting a 150kHz Signal
Table 6. Receiving
INPUT
(V_A - V_B)
≥ +0.2V
≤ -0.2V
Open
OUTPUT
(RO)
1
0
1
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