ROHM Presents the Industry’s First AC/DC Converter ICs with a Built-In 1700V SiC MOSFET

The BM2SCQ12xT-LBZ series integrate 1700V SiC MOSFET, which is also an industry first. This series enables breakthrough energy savings and facilitates efficient AC/DC converter design by resolving many of the issues encountered by designers using discrete solutions. Incorporating a SiC MOSFET and control circuitry optimized for auxiliary power supplies for industrial equipment in a single package significantly reduces the number of parts required when compared to the conventional designs (from 12pcs plus heat sink to a single IC). It also aids to minimizing both the component failure risk and the amount of resources required to develop systems using SiC MOSFETs. In addition, this product enables the improvement of power efficiency by 5% (and decreasing power loss by 28%). These features translate to dramatic reduction in size, improved reliability, and superior power savings in industrial applications.

ROHM is committed to developing not only power semiconductors such as SiC devices but also the ICs for controlling them, and to providing optimized solutions that contribute to greater energy savings and performance in industrial equipment.


Distribution Inventory

SiC MOSFET Advantages

Part No. Supply Voltage Range Normal Operating Current Burst Operating Current Max. Operating Frequency FB OLP VCC OVP Operating Temperature Range
BM2SCQ121T-LBZ VCC : 15.0V ~ 27.5V
DRAIN: 1700V (max.)
2000µA (typ.) 500µA (typ.) 120kHz (typ.) Auto Restart Latch -40ºC to 105ºC
BM2SCQ122T-LBZ Latch Latch
BM2SCQ123T-LBZ Auto Restart Auto Restart
BM2SCQ124T-LBZ Latch Auto Restart

Key Advantages

1. Breakthrough miniaturization is enabled by replacing 12 components and heat sink with a single package

ROHM’s latest products replace up to 12 components (AC/DC converter IC, 800V Si MOSFET x 2, Zener diode x 3, resistor x 6) and the heat sink with a single package, dramatically reducing the number of external parts required. In addition, the high withstand voltage and voltage noise resistance of the internal SiC MOSFET make it possible to reduce the size of components used for noise suppression.

Application Circuit and Adoption Results

2. Development resources and design risks are reduced while providing multiple built-in protection functions that enable superior reliability

The monolithic design reduces the resources required for component selection and reliability evaluation for the clamp and drive circuits while also minimizing component failure risk and simplifying the development effort for SiC MOSFET adoption. In addition, overload protection (FB OLP), overvoltage protection (VCC OVP) of the supply voltage pin, and a high accuracy thermal shutdown function (TSD) (achieved through the built-in SiC MOSFETs) are built in, along with the over current protection and secondary overvoltage protection functions. This enables the incorporation of multiple protection circuits for industrial power supplies that require continuous operation hence leading to a significant improvement in system reliability.

3. SiC MOSFET performance is optimized to achieve dramatically improved power savings

Both internal SiC MOSFET and the built-in gate driver circuit optimized for this SiC MOSFET improve efficiency by as much as 5% over conventional Si MOSFETs (ROHM April 2018 study). Also, a quasi-resonant method is adopted for the control circuit that enables operation at higher efficiency and lower noise than conventional PWM systems, minimizing the effects of noise in industrial equipment.

AC/DC Converter Efficiency Comparison: Si vs SiC

Application Examples

・General-purpose inverters

・AC servos

・PLCs (Programmable Logic Controllers)

・Manufacturing equipment


・Industrial lighting (i.e. street lamps)

Optimized for auxiliary power supply circuits in 400VAC industrial equipment

AC/DC Converter Diagram