Abstract: A low-cost, highly-responsive temperature sensor has a thermistor element surface-mounted in a circuit defined by an electrically-conducting layer of a three-layer circuit substrate to be in close thermal coupling to a metal base layer on an opposite side of the substrate. The base layer is adapted to be disposed in heat-collecting relation to a surface whose temperature is to be monitored. An intermediate layer of the substrate has a binder electrically insulating the thermistor from the metal base layer and has thermally-conducting particles dispersed in the binder to improve thermal coupling of the thermistor to the heat-collecting substrate base layer. The circuit defines terminal pads surface-mounting the thermistor element at one end of the substrate and defines interconnected terminal pads at an opposite end of the substrate which are connected to device lead wires in substantial thermal isolation from the thermistor element.

Abstract: Differentially connected capacitive sensors are mechanically coupled with the flexible capacitor plate of one sensor coupled to the source of pressure to be measured, the flexible capacitor plate of the other sensor coupled to ambient pressure. In a second embodiment, inaccuracies due to forces on the flexible plate are minimized by providing a housing with a tapered inner wall, an O-ring and a support to apply a radial load to the sensor due to clamping action from the tapered housing against the O-ring to provide a seal for the pressure sensing chamber. In a further embodiment, the cost of fabrication of the pressure transducer is minimized by providing the housing as a one piece cup. The electronics are mounted on the exterior surface of the low pressure side of the ceramic capacitor pressure sensing element and sealed in thereat by potting with an epoxy.