Signal transmission device

The utility model discloses a signal transmission device comprising a flexible cable, a first insulating layer, a first conductor layer and a second insulating layer of the flexible cable are stacked in sequence, and a first shielding layer is arranged on the outer side of the first insulating layer and/or the second insulating layer; the first conductor layer comprises a first wire and a first ground wire; a third insulating layer, a second conductor layer and a fourth insulating layer of the flexible circuit board are stacked in sequence, a second shielding layer is arranged on the outer side of the third insulating layer and/or the fourth insulating layer, and the second shielding layer is electrically connected with the first shielding layer; the second conductor layer comprises a second wire and a second ground wire, the second wire is electrically connected with the first wire, and the second ground wire is electrically connected with the first ground wire. The circuit of the flexible circuit board of t