An LED illumination device corresponds to a compact fluorescent lamp and has improved thermal properties. The illumination device includes a transparent tube having an inner wall defining a cavity, a light engine having one or more light emitting diodes, and a driver to drive the light engine. The light engine is disposed at the inner wall of the transparent tube. The arrangement of the light engine and the one or more light emitting diodes at the inner wall of the tube provides improved lighting characteristics. Simultaneously, an improved cooling is provided by the interface surface for conducting heat between the inner wall and the light engine.