Cloud computing and artificial intelligence (AI) are pushing the power of microprocessors, requiring more than a thousand amperes of current. The vertical power delivery (VPD) architecture replaces the state-of-the-art lateral power delivery (LPD) to provide ultra-high current to the microprocessors efficiently. With the VPD architecture, the voltage regulator modules (VRMs) are placed under the processor, requiring low-profile VRMs with high current density to comply with the processor platform’s form factor. However, magnetic components are usually the bottleneck to achieve high-density VRMs. This paper proposes a new twisted core coupled inductor structure, enabling low-profile VRM. The proposed inductor features a high current density (> 1A/mm2) with a height of only 2 mm. Moreover, the proposed inductor achieves negative coupling with a single straight winding, resulting in an extremely small winding resistance ( < 0.05 mΩ). The fabricated two-phase negative coupled inductor is experimentally verified and has a high current handling capability of up to 130 A.
