The invention relates to a buck converter comprising: a pair P.sub.--0 of
switches SB, SH in series and connected to an input terminal B of the
converter by the switch SB, K other additional pairs P.sub.--1,
P.sub.--2, . . . , P_i, . . . P_K-1, P_K of switches in series between
another input terminal A and the switch SH of the pair P.sub.--0, with
i=1, 2, . . . K-1, K, the two switches of the same additional pair P_i
are connected in series via an energy recovery inductor Lr_i; K input
groups, Gin.sub.--1, Gin.sub.--2, . . . Gin_i, . . . Gin_K-1, Gin_K, of
Ni capacitors C each in series; K output groups, Gout.sub.--1,
Gout.sub.--2, . . . Gout_i, . . . Gout_K-1, Gout_K, of Mi capacitors C
each in series. The switches P.sub.--0 and the K additional pairs are
simultaneously controlled by first and second complementary control
signals.