Newly Patented Power Supply Uses Fraction of Capacitance of Linear Supplies

It improves current linearity, and uses high-quality film capacitors instead of electrolytics

Jan 07, 2013, 15:36 ET from RHB Sound Dezign

PHILADELPHIA, Jan. 7, 2013 /PRNewswire/ -- GreenForce™, the first major innovation in power supply technology in decades, has been patented by Bob Backert, of Pennsylvania's RHB Sound Dezign

The GreenForce power supply uses on the order of 1% of the capacitance of conventional linear power supplies. 

Developed initially for audiophile-quality amplifiers, GreenForce has nothing in common with switching supplies, and very little in common with linear supplies.

Less Capacitance Leads to Better Current Linearity

"I wanted a power supply with maximum current linearity," said Mr. Backert.  "Electrolytic capacitors are non-linear in my view, so I felt it was necessary to eliminate them.  To do this, I set out to achieve the absolute minimum capacitance, which would let GreenForce use only the highest quality film capacitors, and yet remain affordable." 

"As a result, if you take an amplifier that operates at 350V and 20mA, which might normally use 100uF in the power supply, with GreenForce it would use less than 1uF," said Mr. Backert.  "We have a popular-brand audiophile preamplifier in our labs now – its power supply went from 40uF to less than 0.22uF when we installed GreenForce."

In fact, GreenForce can power many loads using only Teflon film capacitors, believed by many to be the best capacitors in the world.  The sound quality improvement after installing GreenForce in an amplifier is immediately obvious.

The Green in GreenForce

As it turned out, eliminating lower-quality capacitors not only improved performance, but also had an earth-friendly effect.  This is because electrolytic capacitors contain a chemical sludge that is not friendly to the environment.  In contrast, the high-quality film capacitors used by GreenForce are inert, made from plastic and metal.

Another First: The Proactive Power Supply

The invention uses just six basic parts, together with a transformer in the same position as a linear supply, which achieves isolation from the AC line.    

Unlike traditional power supplies, in which a capacitor passively bleeds power out when the load demands it, GreenForce actually "forces" power into the load.

"The forcing action is proactive," said Mr. Backert, "which we believe makes GreenForce far more nimble in responding to sudden current demands."

Better at High Temperatures and High Radiation

In addition to environmental issues, the electrolytic capacitors used in most linear power supplies have several drawbacks.  They age over time, becoming less and less effective.  They can fail catastrophically, bursting open to leak harmful chemicals onto other sensitive electronics.  And they are polarized, which causes them to fail if connected improperly.  Film capacitors have none of these disadvantages.

Further, electrolytic capacitors are less desirable in high- temperature and high-radiation conditions. They have relatively low voltage ratings compared with film capacitors. And in audio amplifiers, the application for which GreenForce™ was initially invented, electrolytic capacitors simply do not sound as good as film capacitors.


The GreenForce™ power supply can be used in any electric component requiring a conversion from AC to DC. 

The benefits of GreenForce may be most apparent in highly regulated devices requiring linear current. 

Applications include amplifiers, signal processors and measuring or monitoring instruments for military, medical, or other scientific purposes.


GreenForce can be used by any manufacturer via a standard licensing agreement.

For more details, visit

RHB Sound Dezign is an electronics modification firm primarily serving audiophiles, located near Philadelphia, PA.

"Teflon" is a registered trademark of E. I. du Pont de Nemours and Company.

Andy Tebbe
(302) 723-7549

SOURCE RHB Sound Dezign