Voltage booster converter comprising a pair of input terminals A and B for connecting a DC input voltage Vin between these two terminals; a pair P.sub.0 of switches SB, SH in series connected by the switch SB to the input terminal B, the input terminal A being connected across an input inductor Lin to the connection point between the two switches SB and SH in series, each switch SB, SH comprising a control input so as to be placed simultaneously, one in an on state the other in an isolated state; a pair of output terminals C and D, for powering, by an output voltage Vout, a load Rout, the output terminal D being connected to the input terminal B; K other additional pairs P.sub.1, P.sub.2, . . . P.sub.i, . . . P.sub.K-1, P.sub.K of switches in series between the output terminal C and the free side of the switch SH with i=1, 2, . . . K-1, K, the two switches of one and the same additional pair P.sub.i being connected across an energy recovery inductor Lr.sub.1; K input groups, Gin.sub.1, Gin.sub.2, . . . Gin.sub.i, . . . Gin.sub.K-1, Gin.sub.K, of Ni capacitors C of like value each in series, with i=1, 2, . . . K-1, K and Ni=i; K output groups, Gout.sub.1, Gout.sub.2, . . . Gout.sub.i, . . . Gout.sub.K-1, Gout.sub.K, of Mi capacitors C of like value each in series, with i=1, 2, . . . K and Mi=(K+1)-i. The switches of these other K additional pairs are controlled simultaneously by the first and second complementary control signals.