Superpower compared to SuperTeddyReg

How does Belleson Superpower compare with a SuperTeddyReg regulator? We compare to the voltage regulator shown here, called the SuperTeddyReg regulator. Both devices were tested with as nearly identical conditions as possible, with both devices using the same input supply and Vout nominally = 24V for both regulators (STR was 23.5V with the R2 and R3 shown below).

First, as advertised, SuperTeddyReg has excellent noise performance. However, it may be better classified as a low noise voltage reference than as a voltage regulator. A performance comparison using both LTSpice and a breadboard shows that Vout varies with load. A measurement at 700mA (see photo below) shows almost 1V change in Vout, or load regulation = 28dB. Said another way, a 700mA change in Iout results in a 4% change in Vout.

Simulation also shows that ripple increases with load, going from 22µV with a 2.4mA load to 520µV with a 602mA load. For the same conditions (Vin=30V, Vripple=1Vp-p sine wave @ 120Hz), Superpower has essentially unmeasurable ripple at 2.4mA and 5µV at 605mA.

The SuperTeddyReg built and measured (shown below) uses different JFETs and small signal NPNs from the original schematic. The components do not change the primary behavior of the SuperTeddyReg, which is governed by the an open loop topology with no feedback to keep Vout constant with load changes.
SuperTeddyReg schematic as simulated and breadboarded for test.

Dynamic performance was tested with a 700mA current step for both a Superpower device and the SuperTeddyReg circuit. Notice C7, which was added to prevent a low level oscillation. The test circuit was built in a fastidious way on ground plane. The web site states that the circuit "allows a maximum current of around 2.5A" so 700mA should not overtax it.

Superpower, 700mA step

Superpower 700mA dynamic response
Superpower delivering 700mA into 10Ω. The bottom trace shows voltage measured across a 10Ω load resistor that is switched to Vout, about a 7V step (700mA). Top trace shows Vout to ground as current steps from 80mA to 700mA. The scales are the same as the SuperTeddyReg to the right. Notice Vout (top) has a tiny transient but is essentially flat, what we call "regulated."

Superpower 700mA dynamic response
Here is the same test, only the vertical scale of the top trace has been magnified to 5mV per division. Here you can see the true regulation ability of Superpower compared to SuperTeddyReg. While the Teddy moves about 1V for a 700mA step, the Belleson regulator moves about 7mV, which is the result of 10mΩ (yes, ten milli Ohms) in the measurement path.

SuperTeddyReg, 700mA step

SuperTeddyReg measurement of 700mA step
SuperTeddyReg regulator delivering 700mA into 10Ω. Bottom trace shows Vout across a 10Ω resistor. Top trace shows Vout to ground, which ideally should be a flat line at 23.5Vdc. However, notice the 1V per division scale of the top trace, showing that Vout changes almost 1V when the load is applied. This change is a DC shift, not a dynamic effect, due to the lack of feedback in SuperTeddyReg.

SuperTeddyReg simulation of 700mA step
A simulation of the SuperTeddyReg circuit shown above confirms that a regulator with no feedback does not regulate. It shows 1.2V of change in Vout with a 700mA change of output current. No amount of fluffy marketing words will make the measurements change.


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The Industry Standard SPX

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  • 5V to 30V output
  • World's lowest output impedance
  • Superb ripple rejection (135dBV)
  • Instant step response
  • Extreme low noise
  • TO-220 footprint
  • No thermal pad needed!

High Voltage!

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  • Variable output 5V to 450V
  • Up to 500mA output current
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  • Small TO-220 footprint!
  • Low output impedance
  • Fast response
  • Low noise

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SPHP—1000 Watts for your music server!

SPHP, a 10A Superpower with adjustable output voltage from 5V to 100V

  • Same low noise
  • Same blazing step response
  • Same great ripple rejection.
Just lots more current and much higher output voltage. For sale on our order page See more information in the data sheet here.

Build a power supply

A PCB and parts list for building a compact dual positive or positive+negative power supply are on this new page.

Transformer Calculator!

Use the Belleson Transformer Calculator to calculate the minimum Vrms voltage of a transformer for your Superpower based supplies.

It's Official

We're proud to announce the U.S. Patent and Trademark Office has granted patent 8,294,440 to the Superpower design.

Use the Superpower regulator in...

  • Headphone amps
  • DACs
  • Buffers
  • Clocks and reclockers
  • Preamps
  • Microphone preamps
  • Phono stages
  • Phono motors
  • Tube preamps and input stages
  • Line powered guitar effects boxes
  • Anywhere an extremely clean, quiet, dynamic power source is needed