AOS Introduces 80V Half-Bridge MOSFET in AmpStack DFN6x5 Package

Alpha and Omega Semiconductor has introduced the AOPL66801, an 80V MOSFET device that integrates high-side and low-side switches in a single DFN6x5 package. The new part is the first release based on the company's AmpStack packaging technology, which uses vertically stacked die to form a half-bridge.

Both MOSFETs have a maximum RDS(on) of 2.2mΩ at a gate-source voltage of 10V. The high-side device is rated for 304A drain current, while the low-side device is rated for 215A.

Two MOSFETs Stacked in One Package

The AmpStack architecture places two MOSFET die vertically within the DFN6x5 package. They are internally connected as high-side and low-side switches, replacing a half-bridge arrangement built from two separate DFN5x6 MOSFET packages.

AOS positions the design for power conversion systems where PCB area and switching performance are both important. Target applications range from AI power infrastructure to power tools.

The package uses an optimized clip for the switch-node connection between the two MOSFETs. According to AOS, shortening this internal connection reduces parasitic inductance compared with a discrete PCB implementation.

Switch-Node Ringing and Gate Drive

Parasitic inductance between the high-side and low-side devices can contribute to phase-node voltage ringing during fast switching. AOS states that the internal AmpStack connection reduces this inductance, helping to limit ringing and electrical stress on the MOSFETs.

The AOPL66801 also includes a Kelvin sense pin. This provides a separate gate-drive reference path intended to maintain gate-voltage stability during high di/dt switching events rather than sharing the main current path.

AOS says the Kelvin connection is particularly relevant to the high-side drive path, where PCB layout and common-source inductance can affect switching behavior.

Electrical Ratings and Availability

The AOPL66801 is rated for an 80V drain-source voltage and ±20V gate-source voltage. Both internal MOSFETs have typical input capacitance of 4900pF, output capacitance of 1400pF, reverse transfer capacitance of 34pF, and total gate charge of 70nC.

Maximum junction temperature is 175°C.

The AOPL66801 is available now in production quantities. AOS lists a unit price of $6.16 in quantities of 1,000, with a 16-week lead time.

Learn more and read the original announcement at Alpha and Omega Semiconductor's website.

Technology Overview

The AOS AOPL66801 is an 80V half-bridge MOSFET device built in the company's DFN6x5 AmpStack package. Two MOSFET die are vertically stacked and connected as high-side and low-side switches, with an internal switch-node clip intended to reduce parasitic inductance compared with a half-bridge using two separate DFN5x6 MOSFET packages.

Frequently Asked Questions

What is the AOS AOPL66801?

The AOPL66801 is an 80V half-bridge MOSFET device containing high-side and low-side switches in a single DFN6x5 AmpStack package. Both internal MOSFETs have a maximum RDS(on) of 2.2mΩ at VGS = 10V.

How does the AOPL66801 AmpStack package differ from two discrete MOSFETs?

The AmpStack package vertically stacks two MOSFET die and connects them internally as a half-bridge. AOS compares the design with a solution using two separate DFN5x6 MOSFET packages and states that the integrated arrangement reduces PCB area and switch-node parasitic inductance.

Why does the AOPL66801 include a Kelvin sense pin?

The Kelvin sense pin provides a separate gate-drive reference path that is isolated from the main source-current path. AOS states that this helps maintain gate-voltage stability during high di/dt switching and reduces the effect of parasitic inductance on gate-drive performance.