1 Features

• Meets or exceeds TIA/EIA-485-A

• Signaling rate up to 20 Mbps

• 1/8 unit load – up to 256 nodes on a bus

• Thermal shutdown protection

• Typical efficiency > 60% (ILOAD = 100 mA) - see

SLUU469

• Low bus capacitance 7 pF (typical)

• 50-kV/μs typical transient immunity

• Fail-safe receiver for bus open, short, idle

• Logic inputs are 5 V tolerant

• Bus-pin ESD protection

– 11-kV HBM between bus-pins and GND2

– 6-kV HBM between bus-pins and GND1

• Safety and regulatory approvals

– 4242 VPK basic insulation per DIN EN IEC

60747-17 (VDE 0884-17)

– 2500 VRMS isolation for 1 minute per UL 1577

– CSA component acceptance notice 5A, IEC

60950-1 and IEC 61010-1 standards

2 Applications

• Isolated RS-485/RS-422 Interfaces

• Factory automation

• Motor/motion control

• HVAC and building automation networks

• Networked security stations

3 Description

The ISO3086T is an isolated differential line

transceiver with integrated oscillator outputs that

provide the primary voltage for an isolation

transformer. The device is a full-duplex differential line

transceiver for RS-485 and RS-422 applications that

can easily be configured for half-duplex operation by

connecting pin 11 to pin 14, and pin 12 to pin 13.

These devices are ideal for long transmission lines

since the ground loop is broken to allow for a much

larger common-mode voltage range. The symmetrical

isolation barrier of the device is tested to provide 4242

VPK of isolation for 1 minute per VDE between the

bus-line transceiver and the logic-level interface.

Any cabled I/O can be subjected to electrical

noise transients from various sources. These noise

transients can cause damage to the transceiver

and/or near-by sensitive circuitry if they are of

sufficient magnitude and duration. These isolated

devices can significantly increase protection and

reduce the risk of damage to expensive control

circuits.

The ISO3086T is specified for use from –40°C to

85°C.