Building automation equipment monitors and controls environmental systems within a building, including heating, ventilation and air conditioning (HVAC); security video, alarms and access control; fire and safety; metering; and, lighting.
Thermal Sensor Digitizers
Thermocouples and resistance temperature detectors (RTDs) are the most common industrial temperature sensors due to their ability to handle very wide temperature ranges. However, interfacing to these devices is not always easy. They must be properly biased and their signals properly linearized to realize their maximum accuracy and precision. Any loss of signal from these sensors can be a critical problem since they are usually an integral part of the temperature control loop. To help our customers realize simple and reliable solutions to these challenges, we have developed single-chip sensor digitizer solutions for both thermocouples and RTDs. The solutions bias the sensors, handle the cold junction compensation needed for thermocouples, have many built-in fault detections, and provide digital outputs.
Many building automation systems use RS-485/RS-422 transceivers as the physical media layer for communications between the building automation controller and the remotely managed sensors and actuators. RS-485/RS-422 devices use relatively low-cost twisted-pair wiring, and offer fairly high-speed communications over long distances, up to 4000ft—enough to support direct communications links in most buildings.
The adoption of automation and data exchange technologies in smart buildings introduces challenges in energy efficiency, miniaturization, and system reliability. For each challenge, proper power management can improve the design of building automation systems. Highly integrated, high-power buck converter ICs and power modules are ideal for energy efficiency. Low-power, highly integrated power management ICs and fully integrated power modules for highly space-constrained applications are ideal for sensor applications. No-opto isolated flyback converter ICs and highly integrated protection ICs are ideal for safety and reliability applications.
RTD-to-Digital Temperature Sensor InterfaceMAX31865
Provides 0.5°C total accuracy with fault detection and ±45V input protection
4.5 to 60V, 5A, High-Efficiency Step-Down ConverterMAX17506
Includes integrated high-side MOSFET with output from 0.9V up to 0.9 x VIN in a 5mm x 5mm TQFN
2.75kVRMS Isolated RS-485 TransceiverMAX14853
Full-duplex, 500kbps RS-485 with ±35kV ESD protection and integrated transformer driver
Large modern buildings often feature building automation controllers. These controllers often have an architecture similar to that of a programmable logic controller (PLC).
PLC solutions are suitable for use in these controllers.