At the same time, higher performance is also required to reduce energy consumption.
However, reducing the package size also reduces the surface area of the back electrode and the profile, resulting in less heat dissipation. To address this, ROHM's PMDE package improves heat dissipation performance by enlarging the back electrode and thus optimizing the heat dissipation path.
This achieves the same electrical characteristics as conventional packages, but in a smaller package size.
ROHM's patented compact PMDE package features a circuit design equivalent to the conventional SOD-323 type. Revisions to the back electrode and heat dissipation path have enabled ROHM to achieve the same electrical characteristics (i.e., current, non-disruptive voltage) as the standard SOD-123FL package (3.5 mm × 1.6 mm) in a smaller package size, contributing to board miniaturization by reducing the mounting area by approximately 42%. Furthermore, the mechanical strength is approximately 1.4 times greater than that of the SOD-123FL, reducing the risk of solder cracking when voltage is applied to the board and thus ensuring greater assembly reliability.
The PMDE package range consists of eight models in the RBxx8 series of Schottky barrier diodes (SBDs), two models in the RFN series of fast recovery diodes (FRDs), and two models in the VS series of TVSs. These compact diodes enable a wide range of circuit applications.
Looking ahead, ROHM will strive to further improve the quality of its semiconductor devices, from low to high voltage, while continuing to strengthen its distinctive product range to further reduce power consumption and achieve even greater package miniaturization.
(Fig. 2)
PMDE Package Products:
The PMDE package offers the same electrical characteristics as the conventional SOD-123FL package in a smaller package size, ensuring better heat dissipation performance and greater assembly reliability. Furthermore, all automotive-compatible part numbers are rated according to the AEC-Q101 automotive reliability standard. Our new PMDE package product ranges are listed below. (SBD: RBR series only, in mass production since June 2021.)
1. SBD: Features of the RBxx8 Series (New Products)
These SBDs offer low forward voltage along with high efficiency. Ten models in PMDE packages have been added to the RBxx8 series with breakdown voltages from 30 V to 150 V, providing ultra-low reverse current (IR) and stable operation even in high-temperature environments.
RBxx8 Series Range Chart
(Fig. 3)
2. SBD: RBR Series Features (Announced August 2021)
The RBR series balances the compensation ratio between low forward voltage, which is key to improving efficiency, and low reverse current (mass-produced since June 2020). This PDME package series includes 6 different models.
RBR series range table (PMDE package)
(Fig. 4)
3. FRD: RFN Series Features (New Products)
FRDs offer high non-disruptive voltage (up to 800 V) equivalent to that of rectifier diodes, along with excellent trr (reverse recovery time), which is important for high-frequency operation. The RFN series offers the same electrical characteristics as conventional products in a compact PMDE package.
RFN Series Range Table (PMDE Encapsulation)
(Fig. 5)
4. TVS: VS Series Features (New Products)
The TVS is a type of diode that absorbs the sudden voltage surge that occurs during startup or breakdown, and then reduces it to a constant voltage. The VS series supports a wide range of stand-off voltages (VRWM) from 5 V to 130 V.
(32 stand-off voltage ranges are offered between 5 V and 130 V)
VS series range table (PMDE package)
(Fig. 6)
Availability: mass production, available through online distributors Digi-key, Mouser and Farnell AG.
Application examples
(Fig. 7 – 10)
