Driver (150) for a gas discharge lamp (9) comprises: an arrangement of two MOSFET switches (61, 62) connected in series between two input terminals (51a, 52b); an inductor (73) connected in series with said lamp (9), this series arrangement being coupled to a node (P) between said two switches; a control unit (180) providing control signals (S1, S2) to said two switches. During a first commutation interval (41), a lamp circuit current (ILC) has only a first direction while during a second commutation interval (42) said lamp circuit current has only an opposite direction. In each commutation interval (41, 42), during a first operational phase (43) said lamp circuit current has a continuously increasing level while during a second operational phase (44) said lamp circuit current has a continuously decreasing level. The control unit (180) is designed to generate its control signals (S1, S2) such that said two switches are always, switched substantially simultaneously in counter-phase. The mosfets are used in reverse conduction m node also, to avoid body diode conduction (synchronous rectification).

 
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