A circuit (21, 22) to transfer a command signal in a circuit comprising circuit stages which are voltage supplied by different voltage domains (VCC, GND; FS, FG) including a first voltage domain (VCC, GND) comprising first voltage levels represented by a first voltage supply and a first voltage reference, in particular a DC voltage supply and a DC ground, and a second voltage domain (FS, FG) comprising second voltage levels represented by a second voltage supply and a second voltage reference (V FG), in particular a floating supply and a floating ground, and said circuit (21, 22) to transfer a signal operating according to the first voltage domain (VCC, GND) to a stage (HS_DRV, PW1) operating according to the second voltage domain (FS, FG), said circuit (21, 22) to transfer a command signal including a logic component operating according to the second voltage domain (FS, FG) logically driving said stage (HS_DRV, PW1), and a level shifting circuit (22; 32; 42) coupled to the second voltage supply and to the first ground reference, said level shifting circuit (22; 32; 42) including two paths coupled between said second voltage supply and to the first ground reference, each including a high voltage transistor (221a, 221b) coupled through a respective resistor (223a, 223b) to the second voltage supply and through a respective commanded current generator (222a; 222b) to the first ground reference, each path being coupled to a respective input (S,R) of the logic component, said commanded current generator (222a; 222b) being commanded by pulse signals (Tpl, Tp2) generated by a pulse generator on the basis of said command signal, characterized in that said level shifting circuit (32; 42) includes a negative bootstrap circuit (C1, INV1, INV2, C2, INV3, INV4; Cpump, SINV, FINV, 228, 229) including at least a pump capacitor (C1, C2; Cpump) arranged between the current generators (222a; 222b) and the first ground reference and configured to shift at a negative voltage said first ground reference synchronically with the activation of the respective commanded current generator (222a; 222b). a first voltage domain (VCC, GND) comprising first voltage levels represented by a first voltage supply and a first voltage reference, in particular a DC voltage supply and a DC ground, and a second voltage domain (FS, FG) comprising second voltage levels represented by a second voltage supply and a second voltage reference (V FG), in particular a floating supply and a floating ground, and said circuit (21, 22) to transfer a signal operating according to the first voltage domain (VCC, GND) to a stage (HS_DRV, PW1) operating according to the second voltage domain (FS, FG), said circuit (21, 22) to transfer a command signal including a logic component operating according to the second voltage domain (FS, FG) logically driving said stage (HS_DRV, PW1), and a level shifting circuit (22; 32; 42) coupled to the second voltage supply and to the first ground reference, said level shifting circuit (22; 32; 42) including two paths coupled between said second voltage supply and to the first ground reference, each including a high voltage transistor (221a, 221b) coupled through a respective resistor (223a, 223b) to the second voltage supply and through a respective commanded current generator (222a; 222b) to the first ground reference, each path being coupled to a respective input (S,R) of the logic component, said commanded current generator (222a; 222b) being commanded by pulse signals (Tpl, Tp2) generated by a pulse generator on the basis of said command signal, characterized in that said level shifting circuit (32; 42) includes a negative bootstrap circuit (C1, INV1, INV2, C2, INV3, INV4; Cpump, SINV, FINV, 228, 229) including at least a pump capacitor (C1, C2; Cpump) arranged between the current generators (222a; 222b) and the first ground reference and configured to shift at a negative voltage said first ground reference synchronically with the activation of the respective commanded current generator (222a; 222b).