Diodes Optimize complementary MOSFETs for increased buck converter power density

     Diodes Incorporated introduces the complementary dual MOSFET combination DMC1028UFDB designed to increase the power density of DC-DC converters. The new product integrates N-channel MOSFETs and P-channel MOSFETs into a single DFN2020 package. The device is designed for point-of-load converters, providing core voltages from 3.3V down to 1V for ASics. Target applications include Ethernet network controllers, routers, network interface controllers, switches, digital subscriber line adapters, and processors for devices such as servers and set-top boxes.

     The buck converter utilizes a separate pulse width modulation controller and external MOSFETs to increase design flexibility while providing distributed heat dissipation from the switching element. The DMC1028UFDB MOSFET combination optimizes performance to maximize the efficiency of 3.3V to 1V buck converters and drive loads up to 3A. These optimizations include 19mΩ low on-resistance at Vgs=3.3V for low-side N-channel MOSFETs that are on for two-thirds of the switching cycle, and 5nc low gate charge at Vgs=3.3V for P-channel MOSFETs to minimize switching losses.

     The DMC1028UFDB deploys high-side switching elements using P-channel MOSFETs, which simplifies the design and reduces the number of components compared to N-channel MOSFETs that require charging pumps. This combination of complementary dual MOSFETs that integrate P-channel and N-channel devices into a single DFN2020 package doubles the overall power density compared to standalone MOSFETs in the same size package.