First high-speed, multi-channel digital isolators introduced by Silicon Labs,are designed to meet the demands of programmable logic controller (PLC) applications,including industrial I/O modules,CNC machines and servo motor control.

The new Si838x PLC field input isolator family provide a combination of high-speed channels (up to 2 Mbps), exceptional channel integration (up to eight channels per device), bipolar input flexibility, high noise immunity and 2.5k VRMS safety isolation. The Si838x isolators are also ideal for process automation controllers (PACs) used in distributed process control systems.

Silicon Labs’ Si838x isolators are highly integrated single-chip devices providing eight channels of 24 V digital field interface. By “daisy chaining” 16 Si838x isolators in a system design, developers can create PLCs with up to 128 channels supported by a single SPI port on the system’s embedded processor.

The controller interface can be eight parallel channels or a four-port SPI. Developers can configure the SPI for on-the-fly programming for custom de-bounce of noisy signals and for daisy chaining to support high-channel-density PLC designs.

The Si838x isolators feature a flexible bipolar input capability that gives developers a choice of sinking or sourcing inputs. The LED emulator input circuit supports up to eight sinking or sourcing inputs in a single isolator device with no power supply required on the field side. The output interface to the controller supports low-power operation with 2.25 V operation capability.

The Si838x isolators give a high-speed of 1 MHz (2 Mbps), which is essential for servo motor control applications. The isolators also offer best-in-class noise immunity on high-speed channels (50 kV/µs CMTI typical) to enhance system reliability.

Source: Silicon Labs