Ruschkowski Sigurd

Sigurd Ruschkowski was born in Stockholm of German parents. His electronics interest was ignited by his telecom engineering uncle in Hannover, who sent him both a Märklin H0 railway and Graupner RC parts. During his electronics engineering studies he built the usual audio stuff, and in 1986, after finishing the obligatory military service at the telecommunication troops, he started working for RIFA as an SMPS designer.
 
Having a hobby interest that was the same as his work field, he got a bit fed up with electronics, and studied for a masters in engineering physics at the Royal Institute of Technology, and then back to RIFA and later on Ericsson, where he has worked as both employee and consultant in the fields of hardware, software as well as systems design, automated test system design and implementation, team leader for the "shark fin" cell phone, and project manager for the R380 cell phone. 
 
Today Sigurd he has switched fields and now works at several hospitals in Sweden´s capitol doing research and helping hospital employees to turn their inventions into products. 
 
Sigurd holds two world records in straight-away-racing for electrical RC model boats and cars.
 

Passive, Discrete, DC Coupled, Open Loop IV Converters

Sigurd Ruschkowski got inspired by his friend Erno Borbely (who should not need any introduction) to design a discrete I/V converter for his newest DAC. This converter uses a low-value resistor to convert the DAC output current to a low level signal. The signal is then amplified with an open loop discrete low noise amplifier to regular source levels. Unbalanced and balanced output implementations are shown with performance measurements. As part of the setup, a high performance shunt regulator is also presented.