Electronics which can be defined as the science and technology concerned with the development, behaviour and applications of electronic devices and circuits ^[43] was, and still is, fundamental to spacecraft development. Given the limitations of the early launch vehicles, the miniaturisation of devices to control spacecraft payloads and other equipment became a key driver of this development, and as electronic components were made smaller and lighter the complexity of spacecraft increased.

The application of electronics to spacecraft was, in essence, no different from its application to terrestrial devices, as far as they used the same types of components and circuits. In the early days of spaceflight, electronic circuits in space and on the ground used resistors, capacitors, diodes and transistors mounted on printed circuit boards. The differences lay in the way spacecraft electronics, as a discipline, was required to cope with the constraints placed on it by the space environment, and the applications which electronic components and subsystems were required to support in various types of spacecraft. Of course, these differences remain to this day.

The key design constraints on electronic components are led by the two different environments to which they are subjected: first, the launch vehicle environment, which subjects a payload to noise, vibration and acceleration forces, while also placing strict limits on the size and mass of the payload; and second, the space environment, with its inherent vacuum, microgravity, temperature and radiation characteristics.

Although components and subsystems must be designed to withstand the rigours of the launch environment,...