STMicroelectronics has announced that it is launching its new ISO8200B, an isolated power switch that will enable smaller, more robust and energy-efficient controllers for industrial automation equipment. According to ST a wide variety of industrial-automation equipment, as well as general programmable logic controller (PLC) applications, should be able to benefit from the enhanced space savings, user safety, noise immunity, reliability and energy efficiency offered by this new device.
Industrial switches require physical separation, or galvanic isolation, to protect the logic-controlled circuitry from disturbances on the power side, and to ensure user safety. Conventional, discrete optical isolators (opto-couplers) used for this purpose occupy additional pc-board space and are subject to aging and temperature-related degradation driving up ownership costs.
“The ISO8200B isolated high-side switch is the first integrated device from ST to combine galvanically isolated power and logic circuitry in the same package, allowing smaller controllers and lower cost of ownership,” said Matteo Lo Presti, Group Vice President and General Manager, Industrial and Power Conversion Division, STMicroelectronics. “Moreover, as the industry’s first such device to use a pure RF link enabling communication through the isolation layer, the ISO8200B provides superior noise immunity for ultra-robust and reliable operation.”
Inside the ISO8200B, separate logic and power chips are stacked with the layer interposer that provides very high isolation. The inputs are connected directly to a microcontroller or FPGA (Field-Programmable Gate Array), and the device can drive eight output channels connected to any kind of load connected to ground, whether inductive, capacitive or resistive. The ISO8200B meets the RF immunity standard IEC 61000-4-3.
The design of the IC also ensures low quiescent operating current, reducing power dissipation and saving energy compared to a traditional, opto-coupler based solution. In addition, the ISO8200B integrated power switch has very low on-state resistance, which minimises system energy losses and ensures superior thermal performance for enhanced reliability.
The ISO8200B integrates circuitry for fast demagnetization of inductive loads such as motors or heaters, which delivers further space and cost savings. Built-in protection features guard against over-temperature, short circuit, under-voltage, over-voltage, loss-of-ground or loss-of-supply voltage. In addition a fault output allows direct monitoring of correct operation.