ROHM recently created a compact and high-efficiency 20V Nch MOSFET (RA1C030LD), which is optimized for use in tiny devices such as smartphones and wearables like wireless earbuds or other hearing aids.
The increasing power demands of smaller devices has led to larger batteries in recent years. This reduces the amount of space that can be used for mounting components. However, the maximum size of a battery is limited. To ensure efficient battery use, power loss from mounted components must be minimized. This is why MOSFETs are being developed in wafer-level chip size packages (WLCSP). These devices allow for greater miniaturization and maintain the required characteristics. ROHM uses its strengths as an IC producer to dramatically reduce wiring resistance, which has been increasing with traditional discrete processes.
This results in a small power MOSFET with low power loss. The RA1C030LD comes in a DSN1006-3 chip-sized package (1.05 x 0.6mm). This package uses ROHM’s proprietary IC process for low power dissipation and greater miniaturization.
The figure of merit, which expresses the relationship between switching losses and conduction (ON-resistance/Qgd), has been achieved at a 20% industry-leading level. This allows for a smaller board area and higher efficiency in compact devices. ROHM’s unique packaging structure offers insulated protection for side walls, which is not available in standard products that come in the same package without protection. This minimizes the chance of components coming into contact with each other in compact devices. Compact devices are often forced to use high density mounting because of space limitations. It also makes it safer to operate.
ROHM will continue to create products with lower ON resistance in smaller packages. This will help solve social problems such as environmental protection and improve efficiency in compact devices. Part number of the Specifications for Online Distributors.
Type of MOSFET which conducts when a positive current is applied to the Gate relative the Source. Lower steady state loss is achieved when Drain and Source ON resistors are smaller than Pch MOSFETs. Wafer-Level Chip Size Package (WLCSP). This package is extremely compact and the wiring and terminals are made on wafers, before being separated into separate pieces. The package is smaller than general packages, which have wafers cut individually before the components and terminals are formed. This allows for the package to be reduced in size.
ON Resistance This is the resistance value between Drain and Source when the MOSFET’s ON. This value determines the loss of power during conduction. It is smaller than the ON Resistance. Qgd (Gate Drain Charge) This is the amount of charge used to charge the capacitance between Gate and Drain, after the MOSFET switches ON. Lower values enable faster switching, which leads to lower power loss (switching loss).