An analog input module of a programmable logic controller (PLC) used in factory automation is shown in the image on the left side of this slide. This circuit interfaces sensor data from the field to the PLC. Analog inputs received from field transmitters convert a physical quantity such as temperature or pressure to an electrical signal. These input signals can be group isolated or channel-to-channel isolated. Sensor signals are converted to the digital domain and coupled via a digital isolator to the control domain. As the image shows, on the power side, an isolated DC/DC converter derives power from the backplane and generates an isolated power supply for signal-conditioning elements such as the amplifier and ADC, in addition to providing power for the secondary of the isolator. A device with signal and power isolation in one package can help simplify the section of the image within the box. The single chip isolated signal and power solution provides several benefits, including a reduction in board area. The solution size is reduced significantly since the power stage, transformer, rectifier diodes, isolated feedback, and digital data-isolation channels are integrated into one device. Because the digital isolator package dimensions depend on the isolation ratings, creepage, and clearance, it is possible to fit these additional components in the same package, leading to a compact solution. In addition to the surface area reduction, the use of planar transformers enables the Z-dimension or height of the integrated solution to be lower (~3mm) than discrete transformers, which could be two to three times thicker. Another benefit is that integration helps ease the customer’s safety certification. A circuit containing discrete isolation components adds to the customer’s time required for safety-related certification at the system level. With integrated solutions, both signal and power isolation are certified together, resulting in a shorter certification process for the end product. A final benefit is that the system design becomes much simpler with an integrated solution, since the user can integrate the feedback for line/load regulation and all protection mechanisms for the power supply (such as overload and short-circuit protection, thermal shutdown and soft start) on the chip. Boards with bulky transformers perform poorly in vibration tests. Thus, board-level reliability can also improve with an integrated solution. Even though the single chip solution offers these benefits, to be truly useful an integrated data and power isolation solution must offer high efficiency, high power delivery to provide enough current at the output to drive multiple devices and low emissions while offering high isolation performance.