Patent ID: 7446639

Claim:
A micro power converter comprising: a coil substrate including a coil and external electrodes, a power supply IC chip bonded on a front surface side of the coil substrate, and a resin covering the front surface side of the coil substrate and a front surface side of the power supply IC chip; wherein the coil substrate is formed from a magnetic insulator substrate, with coil conductors formed in inner regions on front and back surfaces of the magnetic insulator substrate, and the external electrodes are formed in peripheral regions on the front and back surfaces of the magnetic insulator substrate; wherein the coil conductors formed in the inner regions on the front and back surfaces of the magnetic insulator substrate are connected by first connection conductors to form the coil and the external electrodes formed on the front and back surfaces of the magnetic insulator substrate are connected by second connection conductors; and wherein the second connection conductors are surrounded by the magnetic insulator substrate in the front surface side of the magnetic insulator substrate and a side face of the second connection conductor is not surrounded by the magnetic insulator substrate in the back surface side of the magnetic insulator substrate.