The one-piece power module (12) comprises at least one cut-out metal trace (14), at least one electronic power component (16) electrically connected to the cut-out metal trace, and an electrically insulating material (30; 56) providing the power module with cohesion. The power module presents a cooling face (28) for putting directly into contact with cooling means external to the module. At least a portion of said cooling face (28) comprises the cut-out metal trace.