Designing robust isolated RS-232 data interfaces for harsh industrial applications may now be simpler, thanks to an innovative, integrated approach
News Release from:
Analog Devices
27 September 2012
A key requirement in industrial and instrumentation (I&I) applications is a reliable data interface for inspecting connected systems via a diagnostic port. The RS-232 bus standard is one of the oldest and most widely used physical-layer bus designs in I&I applications.
First introduced in 1962, RS-232 is a single-ended data transmission standard; yet despite rumours of its early demise, it continues to be widely used throughout the industry for communications over a short cable.
To achieve a robust data communications link in harsh industrial environments, the RS-232 diagnostic port must provide an isolated interface between the RS-232 cable network and the connected systems to protect against voltage spikes and ground loops within the noisy environment and improve system reliability.
Power isolation of the RS-232 communication link is obtained by using an isolated DC-to-DC power supply.
An isolation barrier galvanically isolates the RS-232 bus from each system connected to it, allowing digital data to travel between two points but preventing the flow of ground loop currents; this reduces signal distortion and errors by removing noise that gets coupled onto the communications cable.
You can read the rest of this article in the September issue of Electronic Specifier Design by clicking here.
