News: Microelectronics
21 June 2021
ROHM launches first surface-mount AC/DC converter ICs with built-in 1700V SiC MOSFET
Power semiconductor maker ROHM Semiconductor of Kyoto, Japan has launched AC/DC converter ICs with a built-in 1700V silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) along with control circuitry, optimized for industrial applications focusing on auxiliary power supplies for street lamps, commercial air-conditioning systems, general-purpose inverters and for AC servos drives.
An auxiliary power supply is an essential part of industrial applications for delivering different levels of DC voltages for gate drivers and control units but, using existing silicon MOSFET devices, designers cannot achieve higher efficiency and increased output power because of the higher losses of silicon devices. Existing solutions require a heat-sink and additional components that increase both the losses of the devices and also the size of the system through additional space. Designing an auxiliary power supply using existing silicon devices would also be expensive due to a larger bill of materials (BOM).
ROHM’s BM2SC12xFP2-LBZ power ICs are quasi-resonant (QR) AC/DC converters with an integrated 1700V SiC MOSFET in a single compact surface-mount package (TO263-7L, developed specifically for embedded SiC MOSFETs). The ICs are said to be the right fit for industrial auxiliary power supply solutions in terms of efficiency, shortening design time, simplifying the circuitry and reducing additional components through offering integrated solutions. The ICs also increase product reliability by minimizing the risk of component failure, the firm says.
When used in 400VAC 48W output auxiliary power supplies, besides enabling automatic board mounting that was not previously possible, the number of external parts can be significantly reduced compared with standard configurations – from 12 parts (AC/DC converter IC, 800V SiC MOSFET x2, Zener diode x3, resistor x6) plus a heat-sink to just one part.
At the same time, adopting a SiC MOSFET improves power efficiency by up to 5% and minimizes the risk of component failure. This makes it possible to dramatically increase reliability and energy savings in industrial equipment while significantly reducing the mounting area and costs, says ROHM.
In addition, to support designers, ROHM has made available the BM2SC123FP2-EVK-001 evaluation board using the AC/DC BM2SC123FP2-LBZ IC, which delivers power up to 48W at 400VAC without any heat-sink. Test results for the evaluation board show that the output voltage (24V) is constant and independent from the input voltage.
Pricing is $7.20/unit for the BM2SC12xFP2-LBZ ICs (samples, excluding tax) and $238.80/unit for the BM2SC123FP2-EVK-001 evaluation board, via online distributors Digi-Key, Mouser, and Farnell. Samples are available now, with mass production scheduled for October.
