Smart power switches are being used as replacements for relays, often controlling several kilowatts of power at voltages up to 600V. An aircraft may require over a hundred such devices with different performance ratings to protect the wiring, eliminate electro-magnetic interference and ensure full isolation between the control and output. Although it is possible to purchase off-the-shelf devices, a smart switch has to be matched to the system, which ideally can be satisfied by semi-custom manufacture.

GE Aviation has developed a semi-custom facility for the design and manufacture of smart power switches, using proven building blocks (including matched transistor modules, sense resistors, isolating transformers and ASICs) which are customised to suit a particular requirement for power and protection.