For higher power density of power electronics converters, the integration of passive into the printed circuit board (PCB) is a low cost and integral manufacturing approach. The passive substrate concept for power electronics is proposed in this paper. Based on it, the converter level packaging can be implemented. The commercially available ferrite materials with low high frequency loss can be embedded in the PCB. Thus, transformers and inductors can be entirely integrated in the PCB. The configuration and manufacturing processes of the embedded passive substrate are described. Accordingly, the synchronous full-bridge bus converter with 12 V/26 A output is designed and manufactured using the passive substrate. The electrical and thermal characteristics of the passive substrate are illustrated. The thin converter, better thermal performance and high power density can be achieved.