TO-3 at Motorola around 1955. The lead spacing was originally intended to allow plugging the device into a then-common tube socket. The metal package can be attached to a heat sink, making it suitable for devices dissipating several watts of heat. Thermal compound is used to improve heat transfer between the device case and the heat sink. Since the device case is one of the electrical connections, an insulator may be required to electrically isolate the component from the heatsink. Insulating washers may be made of mica or other materials with good thermal conductivity. The case is used with high-power and
Parasitic element (electrical networks) is not always adequate. For instance, the inter-winding capacitance mentioned above is really a distributed element along the whole length of the winding and not a capacitor in one particular place. Designers sometimes take advantage of parasitic effects to achieve a function in a component, see for instance helical resonator. Non-linear parasitic elements can also arise. The term is commonly used to describe parasitic structures formed on an integrated circuit whereby an unwanted semiconductor device is formed from p-n junctions which belong to two or more intended devices or functions. Parasitic element (electrical networks) In electrical networks, a parasitic element