A rugged new temperature sensor

This paper presents a rugged new tesperature sensor. The development effort was centered on a cooling system application, but the principles of design and fabrication are broadly applicable. In its simplest form, the sensor is a hybrid circuit potted with epoxy into a threaded steel shell for mounting, as shown in Figure 1. The hybrid circuit in turn is basically a porcelain enamel coated steel core on which the electronic elements are printed and fired. The nature of the hybrid circuit will be fully detailed below. We will start with a discussion of the technologies involved in fabricating the product and then go into the properties of the devices themselves.