Chip in oil sensor means smarter, more compact desig

Designers of industrial pumps, valves and filters are under increasing pressure to integrate the latest pressure sensors into their designs without increasing the overall dimensions of their equipment

Problem: . Therefore, the smaller the sensor manufacturers can produce their products, the better. Solution: Dorchester-based firm Keller UK has designed a miniature pressure sensor called 'CIO' which stands for 'chip in oil' technology. The device is a significant breakthrough. The design incorporates an amplifier within the actual oil-filled sensor housing where the programmable amplifier-ASIC is mounted and contacted beside the actual pressure measuring element on the same glass feed-through. As well as leading to a smaller overall design, integrating the entire measuring chain (sensor and electronics) into one housing also reduces the device's susceptibility to interference, therefore increasing working reliability. And compared with a 'one-chip' solution, keeping the pressure element apart from the programmable amplifier offers high flexibility in the realisation of different measuring ranges and adjustment to different customer requests. CIO is designed for a standardised voltage signal (0.5 to 4.5V) which is carried outward via three pins. One of the pins can be used for remote programming of the amplifier by Keller. Applications: Due to its ability to control manufacturing processes, CIO technology is suitable for medium and high volume applications in the industrial, automotive and consumer products markets. The small size of the measuring chain opens up fantastic possibilities with respect to miniaturisation and the design of the housing. The smallest steel-encapsulated, calibrated transmitter is currently 9.5mm in diameter, with a height of 4.2mm, so these systems are best suited for integration into valves, filters, pumps, actuators, manifolds, controllers, dataloggers and other devices where minimal fitting space for sensor technology is a must. DP