Output Impedance vs. Frequency

What is Superpower's output performance under load? Amazing! Here is a graph of Zout vs. frequency, showing a 7mΩ maximum impedance while delivering 100mA at 40KHz. This is measured on a typical production SPL78 with 5V out.

Zout vs. frequency

How do we get such amazing performance? Sorry, that's a secret. But we can tell you how we measured it—we connected a resistor between the regulator output and a sine wave voltage source, then used a spectrum analyzer to measure the variation in regulator output voltage, which ideally is zero. The difference from zero equates to the output impedance of the regulator.

Test conditions

DC load = 5mA
voltage at load resistor = (5VDC - 5Vpp)
dB measurements relative to 200mV full scale
Frequency 50Ω load (100mA pk-pk)
10Hz -80dB
100Hz -85dB
1KHz -83dB
5KHz -74dB
10KHz -71dB
20KHz -67dB
40KHz -63dB

We know the current and the voltage so the values above are used to calculate output impedance. Using the spectrum analyzer full scale value of 0.2Vpp, we see the following values for output impedance vs. frequency:

Frequency 50Ω load (100mA pk-pk)
10Hz 1.0mΩ
100Hz 0.56mΩ
1KHz 0.71mΩ
5KHz 2.0mΩ
10KHz 2.82mΩ
20KHz 4.47mΩ
40KHz 7.08mΩ

Superpower Zout is low and flat across the entire audio band. We dare you to find or build a better regulator! Below is a capture of the 20KHz measurement spectrum. Note that the noise floor is due to the spectrum analyzer, not the Superpower.

Superpower, 100mApk-pk load at 10KHz

Superpower output, 10KHz 50mA load
Spectrum of Superpower driving 100mA pk-pk into 50Ω.

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SPZ, a small 3A SPJ replacement that fits into the space for a monolithic TO-220.

  • Same low noise
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  • More current: 3A
AND it's small enough to directly replace a LM1117 or LM7805! Order now from our store.

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. Now for sale on our order page See more information in the data sheet here.

Authorized Upgrade Centers

Always wanted to improve your system but modifying it makes you nervous? Now you can let a professional do it! Go to our Authorized Upgrade Centers page to find companies that can replace your existing regulators with Belleson Superpower.

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