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).