The patent us 2010/0073978 is clearly NOT an invention of a German company. To see how it had been used in volt meters in 1998, visit: http://www.chipinfo.ru/literature/radio/199801/p29.html
To have the material proof of the working bipolar transistor rectifier bridge exactly as shown on patent drawings, I can provide a power supply of my grandfather's radio, made in 1965. The synchronous rectifiers on germanium transistors were especially efficient at the time.
The us20100073978 is a common knowledge and not an invention of the 21st century.