Alpha and Omega Semiconductor has introduced two power MOSFETs aimed at AI server DC-DC stages: the AONC40202 (25 V) and AONC68816 (80 V). Both devices come in a DFN 3.3 x 3.3 package with double-sided cooling and a source-down layout, targeting intermediate bus converter (IBC) applications where power density and thermal headroom are constant constraints.
The AONC40202 and AONC68816 use an optimized top-clip design for the exposed drain contact, creating a double-sided thermal interface intended to move heat to heatsinks more effectively than single-sided cooling packages. In this package, the company lists a maximum top-case thermal resistance (Rthc-top(max)) of 0.9 °C/W, tied to the large top clip used in the construction.
On electrical ratings, AOS lists the AONC40202 with continuous current capability up to 405 A and a maximum junction temperature of 175° C. The source-down approach is also meant to make PCB implementation easier in high-current layouts: AOS points to a larger source contact to the PCB, plus a center-gate pin layout intended to simplify routing and minimize the gate driver connection.
For data center power designers, packaging details like double-sided cooling and low thermal resistance often matter as much as the silicon, because they directly affect heatsink sizing, airflow requirements, and how hard you can push switching stages before you run out of junction temperature margin. But the payoff depends on the full mechanical stack-up—board copper, vias, TIM selection, and heatsink flatness—so real-world results will hinge on execution, not just the package spec.
“AOS designed these latest MOSFETs to specifically satisfy intensifying AI server power needs,” said Peter H. Wilson, Sr. Director of MOSFET product line at AOS, adding that the DFN 3.3 x 3.3 double-sided cooling source-down packaging delivers “superior heat transfer and thermal performance compared to traditional DFN 3.3 x 3.3 packaging solutions.” AOS also says the parts use its AlphaSGT Silicon Technology.
The AONC40202 and AONC68816 are available in production quantities with a lead time of 14–16 weeks. In 1,000-piece quantities, AOS lists unit pricing at $1.85 for the AONC40202 and $1.95 for the AONC68816.
Source: Alpha and Omega Semiconductor
