ADM3071EARZ Analog Devices Inc, ADM3071EARZ Datasheet - Page 15

• Manufacturer Part Number: ADM3071EARZ
• Description: IC TXRX RS-485 3.3V FD 8-SOIC
• Manufacturer: Analog Devices Inc
• Type: Transceiverr

Specifications of ADM3071EARZ

• Number Of Drivers/receivers: 1/1
• Protocol: RS422, RS485
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Device Type: Transceiver
• No. Of Drivers: 1
• Supply Voltage Range: 2.97V To 3.63V
• Driver Case Style: SOIC
• No. Of Pins: 8
• Operating Temperature Range: -40°C To +85°C
• Svhc: No SVHC (18-Jun-2010)
• Package: RoHS Compliant
• Interface Type: RS422, RS485
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

CIRCUIT DESCRIPTION
The ADM307xE series are high speed transceivers for RS­485
and RS-422 communications. Each device contains one driver
and one receiver. All devices feature fail-safe circuitry, which
guarantees a logic high receiver output when the receiver inputs
are open or shorted or when they are connected to a terminated
transmission line with all drivers disabled (see the Receiver Fail-
Safe section). The ADM307xE also feature a hot-swap capability,
allowing line insertion without erroneous data transfer (see the
Hot-Swap Capability section). The ADM3070E/ADM3071E/
ADM3072E feature reduced slew rate drivers that minimize
EMI and reduce reflections caused by improperly terminated
cables, allowing for error-free data transmission at rates up to
250 kbps.
The ADM3073E/ADM3074E/ADM3075E also offer slew rate
limits, allowing transmit speeds up to 500 kbps. The ADM3076E/
ADM3077E/ADM3078E driver slew rates are not limited, making
possible transmit speeds of up to 16 Mbps. The ADM3072E/
ADM3075E/ADM3078E are half-duplex transceivers; the
ADM3070E/ADM3071E/ADM3073E/ADM3074E/ADM3076E/
ADM3077E are each full-duplex transceivers. All devices operate
from a single 3.3 V supply. Drivers are output short-circuit
current limited, and thermal shutdown circuitry protects
drivers against excessive power dissipation. When activated,
the thermal shutdown circuitry places the driver outputs into
a high impedance state.
FUNCTION TABLES
ADM3070E/ADM3073E/ADM3076E
Table 8. Transmitting Truth Table
RE
X
X
0
1
1
2
Table 9. Receiving Truth Table
RE
0
0
0
1
1
1
2
X = don't care.
High-Z = high impedance.
X = don't care.
High-Z = high impedance.
1
1
ADM3070E/ADM3071E/ADM3072E/ADM3073E/ADM3074E/ADM3075E/ADM3076E/ADM3077E/ADM3078E
Receiving Inputs
Transmitting Inputs
DE
1
1
0
0
DE
X
X
X
1
0
1
1
1
DI
1
0
X
X
1
1
A − B
≥ −50 mV
≤ −200 mV
Open/shorted
X
X
1
1
Receiving Outputs
Y
1
0
High-Z
Shutdown
Transmitting Outputs
2
RO
1
0
1
High-Z
Shutdown
Z
0
1
High-Z
Shutdown
2
Rev. E | Page 15 of 20
2
ADM3071E/ADM3074E/ADM3077E
Table 10. Transmitting Truth Table
DI
1
0
Table 11. Receiving Truth Table
A − B
≥ −50 mV
≤ −200 mV
Open/shorted
ADM3072E/ADM3075E/ADM3078E
Table 12. Transmitting Truth Table
RE
X
X
0
1
1
2
Table 13. Receiving Truth Table
RE
0
0
0
1
1
1
2
RECEIVER FAIL-SAFE
The ADM307xE family guarantees a logic high receiver output
when the receiver inputs are shorted, open, or connected to a
terminated transmission line with all drivers disabled. This is
done by setting the receiver input threshold between −50 mV
and −200 mV. If the differential receiver input voltage (A − B)
is greater than or equal to −50 mV, RO is logic high. If A − B
is less than or equal to −200 mV, RO is logic low. In the case
of a terminated bus with all transmitters disabled, the receiver
differential input voltage is pulled to 0 V by the termination.
With the receiver thresholds of the ADM307xE family, this
results in a logic high with a 50 mV minimum noise margin.
X = don't care.
High-Z = high impedance.
X = don't care.
High-Z = high impedance.
1
1
Transmitting Inputs
Transmitting Input
Receiving Input
DE
0
0
0
1
0
Receiving Inputs
DE
1
1
0
0
A − B
≥ −50 mV
≤ −200 mV
Open/shorted
X
X
1
1
DI
1
0
X
X
1
1
Y
1
0
RO
1
0
1
A, Y
1
0
High-Z
Shutdown
Transmitting Outputs
Transmitting Outputs
Receiving Output
RO
1
0
1
High-Z
Shutdown
2
Receiving Output
2
Z
0
1
B, Z
0
1
High-Z
Shutdown
2