An electronic assembly comprises a rotation device comprising a fixed platform defining a through hole. An annular groove is formed in the inside wall of the fixed platform. A first transmission element seats a plurality of teeth. A second transmission element is located in the through hole, and comprises a threaded axis portion and a toothed portion meshing with the plurality of teeth. A third transmission element comprises a rotation portion rotatably mounted in the interior of the annular groove of the fixed platform. A threaded hole is defined in the rotation portion, and is configured for cooperating with the threaded axis portion. A driver source is fixed on the fixed platform and is configured for rotating the first transmission element. An electronic device is mounted on the third transmission element.