TI ISOW1412DFMR

The ISOW14x2 devices are galvanically isolated RS-485/RS-422 transceivers with an integrated isolated DC/DC converter, eliminating the need for a separate isolated power supply in space-constrained isolated designs. The low-emission, isolated DC/DC converter complies with the CISPR 32 Class B radiated emission standard, using only two ferrite beads on a simple two-layer PCB. An additional 20mA output current can be used to power other circuits on the board. The integrated 2Mbps GPIO channel helps eliminate any additional digital isolators or optocouplers for diagnostics, LED indication, or power monitoring. Two data rate options are available: the ISOW1412 is optimized for a maximum of 500kbps, and the ISOW1432 is suitable for a maximum data rate of 12Mbps. Apart from bypass capacitors, these devices do not require any other external components to implement an isolated RS-485 port, making them ideal for long-distance communication. Isolation breaks the ground loops between communication nodes, resulting in a larger common-mode voltage range. Both the signal and power paths are isolated at 5kVRMS according to UL1577 and comply with the enhanced and basic isolation requirements of VDE, TUV, CSA, and CQC. The ISOW14x2 can operate from a single power supply of 3V to 5.5V by connecting V10 and VDD together on the PCB. If a lower logic level is required, the 1.71V to 5.5V logic supply (V10) can be separated and independent from the 3V to 5.5V power converter supply (VDD). These devices support a wide operating ambient temperature range from –40°C to +125°C and are available in a 20-pin DFM (SOIC-20 footprint-compatible package) with a creepage and clearance of at least 8mm.

• Meets or exceeds TIA/EIA-485A standard requirements
• ISOW1412: 500kbps
• ISOW1432: 12Mbps
• Low-emission, low-noise integrated DC/DC converter compliant with CISPR 32 Class B and EN 55032 Class B with margin on 2-layer PCB
• 25MHz low-frequency power converter for low-noise performance
• Additional 2Mbps GPIO channel
• High-efficiency output power
  • Typical efficiency: 46%
  • VISOOUT accuracy: ±5%
  • Additional output current: 20mA
• Separate power supplies for RS-485 and DC/DC
  • Logic supply (V10): 1.71V to 5.5V
  • Power converter supply (VDD): 3V to 5.5V
• RS-485 and PROFIBUS compatible
  • Open, short, and idle bus failsafe protection
  • 1/8 unit load: up to 256 bus nodes
  • Glitch-free power-up and power-down
• Enhanced and basic isolation options
• High ESD bus protection
  • HBM: ±16kV
  • IEC 61000-4-2 contact discharge: ±8kV
• Operating temperature range: -40°C to 125°C
• Current limiting and thermal shutdown
• 20-pin wide-body SOIC package
• VDE enhanced and basic insulation per DIN VDE V 0884-11:2017-01
• UL 1577 component recognition program
• IEC 62368-1, IEC 61010-1, IEC 60601-1, and GB 4943.1-2011 certifications

• Factory automation
• Building automation
• Industrial transportation
• Photovoltaic inverters, protective relays
• Motor drives