Smart power switch with integrated diagnostics boosts reliability of 24-V industrial equipment

November 08, 2012 // By Paul Buckley
Infineon Technologies AG has introduced its second generation ISOFACE galvanic isolated, 8-channel high side switch for 24 V industrial control and automation applications.

The new ISO2H823V delivers extensive integrated diagnostics to provide visibility into equipment status and thus enables a significant reduction of costly equipment down times. The device isolates the low-voltage, control side components of an industrial controller from the output channels directed to the shop floor.

Typical solutions for galvanic isolation between the control and process side of industrial equipment utilize opto-couplers, which have limited operating temperature range and are subject to aging and temperature drift effects. The ISO2H823V IC provides 2.5 kV isolation (compliant with IEC 61131-2 requirements), higher operating temperature range, and digital power and control functions to drive eight output channels at 600mA each. This results in superior robustness and a completed PCB design that is typically one-half the size of a design using opto-couplers.

Applications for the new IC cover the spectrum of 24V industrial control systems, including Programmable Logic Controllers (PLC), Distributed Control Systems, Industrial PCs and general control equipment. In systems where continuous operation is vital – such as large scale chemical plants, production lines and heavy equipment in field applications – the integrated diagnostic features play a critical role in minimizing unscheduled downtime and speeding any repair that may become necessary.

“In industrial processes, downtime on a single machine may lead to line stoppage and re-start processes that require hours to resume production, resulting in significant production loss and waste,” said Thomas Schmidt, Director Application Marketing at Infineon Technologies. “By providing extensive on-chip diagnostics to give visibility into real-time conditions on the power switch, equipment suppliers can deliver more robust, reliable and repairable control electronics to minimize surprises for users of industrial equipment.”

On-chip diagnostics of the ISO2H823V include channel-level detection of open load, short circuit conditions and over temperature operation. On IC-level, the device monitors supply voltage, output status, over temperature conditions and transmission errors. The depth and range of system information provided enables preventive maintenance and the ability to avoid abrupt shutdown