GENERAL DESCRIPTION

The ADM2795E is a 5 kV rms signal isolated RS-485 transceiver that features up to ±42 V of ac/dc peak bus overvoltage fault protec-tion on the RS-485 bus pins. The device integrates Analog Devices, Inc., iCoupler® technology to combine a 3-channel isolator, RS-485 transceiver, and IEC electromagnetic compatibility (EMC) transient protection in a single package. The ADM2795E is a RS-485/RS-422 transceiver that integrates IEC 61000-4-5 Level 4 surge protection, allowing up to ±4 kV protection on the RS-485 bus pins (A and B). The device has IEC 61000-4-4 Level 4 EFT protection up to ±2 kV and IEC 61000-4-2 Level 4 ESD protection on the bus pins, allowing this device to withstand up to ±15 kV on the transceiver interface pins without latching up. This device has an extended common-mode input range of ±25 V to improve data communication reliability in noisy environments. The ADM2795E is capable of operating over wide power supply ranges, with a 1.7 V to 5.5 V VDD1 power supply range, allowing interfacing to low voltage logic supplies. The ADM2795E is also fully TIA/EIA RS-485/RS-422 compliant when operated over a 3 V to 5.5 V VDD2 power supply. The device is fully characterized over an extended operating temperature range of −40°C to +125°C, and is available in a 16-lead, wide-body SOIC package.

FEATURES

5 kV rms isolated RS-485/RS-422 transceiver

±42 V ac/dc peak fault protection on RS-485 bus pins

Certified Level 4 EMC protection on RS-485 A, B bus pins

IEC 61000-4-5 surge protection (±4 kV)

IEC 61000-4-4 electrical fast transient (EFT) protection (±2 kV)

IEC 61000-4-2 electrostatic discharge (ESD) protection

±8 kV contact discharge

±15 kV air discharge

IEC 61000-4-6 conducted radio frequency (RF) immunity (10 V/m rms)

Certified IEC 61000-4-x immunity across isolation barrier

IEC 61000-4-2 ESD, IEC 61000-4-4 EFT, IEC 61000-4-5 surge, IEC 61000-4-6 conducted RF immunity, IEC 61000-4-3 radiated immunity, IEC 61000-4-8 magnetic immunity

RS-485 A, B pins human body model (HBM) ESD protection: >±30 kV

Safety and regulatory approvals (pending)

CSA Component Acceptance Notice 5A, DIN V VDE V 0884-10, UL 1577, CQC11-471543-2012

TIA/EIA RS-485/RS-422 compliant over full supply range

3 V to 5.5 V operating voltage range on VDD2

1.7 V to 5.5 V operating voltage range on VDD1 logic supply

Common-mode input range of −25 V to +25 V

High common-mode transient immunity: >75 kV/μs

Robust noise immunity (tested to the IEC 62132-4 standard)

Passes EN55022 Class B radiated emissions by 6 dBμV/m margin

Receiver short-circuit, open-circuit, and floating input fail-safe

Supports 256 bus nodes (96 kΩ receiver input impedance)

−40°C to +125°C temperature option

Glitch free power-up/power-down (hot swap)

APPLICATIONS

Heating, ventilation, and air conditioning (HVAC) networks

Industrial field buses

Building automation

Utility networks