±15kV ESD-Protected, ±60V Fault-Protected,
10Mbps, Fail-Safe RS-485/J1708 Transceivers
Function Tables
Table 1. MAX3440E/MAX3441E Fault Table
INPUTS
OUTPUTS
A-B
VID DIFFERENTIAL
INPUT VOLTAGE
COMMON-MODE
VOLTAGE
RO
FAULT
CONDITIONED
BY DELAY
≥0.45V
<0.45V and ≥0.27V
<0.27V and ≥-0.05V
≤-0.05V and ≥-0.2V
≤-0.2V and >-0.27V
≤-0.27V and >-0.45V
≤-0.45V
X
≤12V and ≥-7V
<-7V or >+12V
1
1
1
Indeterminate
(Note 1)
0
0
0
Indeterminate
0
Indeterminate
1
1
1
Indeterminate
0
1
X = Don’t care.
Note 1: Receiver output may oscillate with this differential input condition.
FAULT CONDITION
Normal operation
Indeterminate
Low-input differential voltage
Low-input differential voltage
Low-input differential voltage
Indeterminate
Outside common-mode voltage range
Table 2. MAX3440E/MAX3441E
(RS-485/RS-422)
INPUTS
DE/RE
0
1
1
X = Don’t care.
TRANSMITTING
OUTPUTS
DI
A
B
X
High-Z
High-Z
0
0
1
1
1
0
Table 3. MAX3442E/MAX3443E
(RS-485/RS-422)
TRANSMITTING
INPUTS
OUTPUTS
RE
DE
DI
A
B
0
0
X
High-Z
High-Z
0
1
0
0
1
0
1
1
1
0
1
0
X
Shutdown Shutdown
1
1
0
0
1
1
1
1
1
0
X = Don’t care.
Table 4. MAX3444E (J1708) Application
INPUTS
TXD
DE
0
1
1
1
0
0
1
0
TRANSMITTING
OUTPUTS
A
B
High-Z
High-Z
High-Z
High-Z
0
1
High-Z
High-Z
CONDITIONS
—
—
—
Dominant state
Recessive state
Table 5. MAX3440E/MAX3441E
(RS-485/RS-422)
RECEIVING
INPUTS
DE/RE
(A - B)
0
≥-0.05V
0
≤-0.2V
0
Open/shorted
1
X
X = Don’t care.
OUTPUTS
RO
1
0
1
High-Z
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