Research on thin-film array non-DC-bias integrated magnetics in 4-phase VRM

In order to eliminate DC-bias, this paper presents array type integrated magnetics of 4 phase voltage regulator module (VRM). This paper studies the inductorspsila coupling coefficient of array type integrated magnetics affected on steady current and dynamic response of VRM and analyses the principle of how array type integrated magnetic component eliminate DC-bias with the method of combining ldquofieldrdquo and ldquocircuitrdquo. Equivalent circuit of array type integrated magnetics is deduced. This paper not only designs the structure of thin-film of array type integrated magnetics but also gives the electromagnetism design method of thin-film array type integrated magnetics. The electric circuit simulation and finite element simulation results show that the DC-bias of thin-film array type integrated magnetics is eliminated. Coupling coefficients of the inductors can be changed by attaching magnetic cores. The further simulation and experiment proves that the thin-film array type integrated magnetics have many advantages.