| 摘要 |
<p>A transformer (30) comprises: first and second printed circuit board substrates, the first printed circuit board substrate (32) including at least one first substrate layer (34) having a dielectric relative permittivity of less than or equal to 3.5 and the second printed circuit board substrate including at least one second substrate layer (70) having a dielectric relative permittivity that is higher than the dielectric relative permittivity of the or each first substrate layer (34); and a plurality of electrically conductive traces, at least one electrically conductive trace being patterned on a surface of the first substrate layer (34) or one of the first substrate layers (34) to form a second winding portion (52) and at least one other electrically conductive trace being patterned on a surface of the second substrate layer (70) or one of the second substrate layers (70) to form a first winding portion (50), the first and second winding portions (50,52) defining mutually coupled first and second windings, wherein the first winding is formed by one or more first winding portions (50), the second winding is formed by one or more second winding portions (52), the second winding is formed on the first substrate layer (34) or at least one of the first substrate layers (34), and the first winding is formed on the second substrate layer (70) or at least one of the second substrate layers (70).</p> |
