Renesas Technology America, Inc. announced the RJK0383DPA, a dual-type power MOSFET that is said to enable smaller, higher-efficiency synchronous-rectification dc-dc converters for generating various supply voltages in communication devices and laptop PCs. The device integrates high-side and low-side power MOSFETs and a Schottky barrier diode in a compact (5.3 x 6.2 x 0.8mm, max²) package with high thermal conductivity. In a synchronous-rectification circuit converting a 12Vdc input to a 1.1Vdc output at 600 kHz switching frequencies, it achieves what is described as an industry-best efficiency rating of 91.6%. Output current doubled from earlier dual-type power MOSFETs from Renesas.
According to the company, the RJK0383DPA has two important benefits. It uses a small WPAK³ package that is said to reduce the chip mounting area to about half that of a dual-package power MOSFET configuration, offering the same level of power supply efficiency. It also allows the device to deliver more output current. Smaller synchronous-rectification dc-dc converters are thus enabled, facilitating the higher mounting densities eagerly sought in mobile devices and other products in which small size adds convenience.
The high-side power MOSFET in the RJK0383DPA has a drain-gate load (Qgd) of only 1.5nC (at VDD=10V) for a fast switching speed and correspondingly high efficiency. The device’s low-side power MOSFET has a low on-resistance³ (RDS (on)) of 3.7mΩ (typical, at 4.5V) that reduces power loss. Additionally, the device integrates a Schottky barrier diode (SBD) that is connected via low-inductance wiring to the low-side power MOSFET. This design speeds up the switching of current flow to the SBD during the dc-dc converter’s dead time, for less power loss. It also suppresses voltage spikes during switching, thereby reducing noise. On-resistance is about 30% lower, while the opposing characteristics of gate charge capacitance (Qg) and drain-gate load (Qgd) are approximately 27% and 30% lower, respectively.
Besides the RJK0383DPA, Renesas is developing two other dual-type power MOSFETs having different output current ratings, the RJK0384DPA and RJK0389DPA. Further into the future, more products suitable for other dc-dc converter power supply specifications are under development in response to the needs of the market.
The RJK0383DPA is priced at $0.89.