The present invention is based on a regulation circuit (200a, 200b) for making available a constant current supply on the basis of a transformer principle, in which there flows through the luminescent diodes (D1, . . . ,DN) a triangular a.c. current (I.sub.D) varying periodically around a d.c. current value. With this method it is afforded by means of a circuitry provision that both the charging and also the discharging current (I.sub.L1) of an inductive reactance (X.sub.L1) connected in series to the luminescent diodes (D1, . . . ,DN), functioning as a storage choke (L1) for filtering of mains harmonics, flows as diode current (I.sub.D) through the luminescent diodes (D1, . . . ,DN). The advantage of this method consists in a significant reduction of the overall power loss (P.sub.V, ges) of the LED illumination module (100). According to one exemplary embodiment of the invention the ceramic circuit board (102) of the LED illumination module (100) in accordance with the invention has a direct mains current supply (104, 108), which for protection from mechanical damage is accommodated in a transparent housing (106) having a highly transparent polymer mass (110) serving as optically active lens surface.