The disclosure relates to a printed circuit assembly, PCA, comprising: a printed circuit board, PCB; a group of components comprising an emitter, a detector and an integrated circuit, IC wherein the components are electrically bonded to the PCB, and the emitter and the detector are electrically connected to the integrated circuit via the PCB, the integrated circuit is further configured to control operation of the emitter and the detector in the same group, and a first coating covering at least one of the components in the group, wherein the first coating is made of an optically transparent material. The disclosure also relates to a method for fabricating a printed circuit assembly, and a touch sensitive system comprising the printed circuit assembly.