Energy recovery circuit enables ultra high efficiency claims ST
1 min read
STMicroelectronics has released details of a patented high efficiency circuit and dedicated optimised power components. The company claims the design increases efficiency by as much as 2% at approximately half the price of a solution using SiC devices.
According to ST, the new technology, called BC2 (Back Current Circuit), will produce cost savings, while helping designers comply with the highest power efficiency standards. The Power Factor Correction (PFC) circuits typically combine a power mosfet, a rectifier diode, an inductor, and a capacitor.
The circuit now allows competitively priced silicon diodes to be used in preference to SiC devices in boost or buck converters inside solar inverters or SMPS applications such as desktop pcs, servers and telecom base stations. Where the low recovery current of an SiC boost diode helps to minimise the mosfet switching on losses, BC2 removes these losses and recycles the energy linked to the recovery of the boost diode. Compared to a standard circuit, the new topology requires one additional inductor and three optimised diodes.
To enable BC2 to be implemented in new power supply designs, ST has announced a range of six silicon based rectifiers and free wheel diodes optimised for this application:
• STTH8BC060D/STTH8BC065DI, STTH10BC065CT and STTH16BC065CT - 600 and 650V rectifier diodes, offering current ratings of 8, 10 and 16A, respectively;
• STTH3BCF060U and STTH5BCF060 - 600V free-wheel diodes offering current ratings of 3 and 5A, respectively.
Used in kits, ST says these diodes enable the design of competitive high efficiency circuits up to 2kW.
