Amazing line regulation thanks to extreme isolation
With only two internal connections to the raw DC input, Superpower
has superb line
regulation almost by
definition. The novel output pre-driver allows fast, accurate control
of the output voltage based only on the internal reference voltage and
not on unwanted input signal changes. It also works over a broad
frequency band, not just the audio bandwidth.
The graphs below illustrate line regulation as the rejection of 60 and 120 Hz line noise from a raw voltage supply, also rejection of other frequencies. You may have to order one to convince yourself it really is this good.
No-load spectrum—input (red), output (blue)
This spectrum illustrates the line rejection of 60Hz and its
harmonics at 180Hz, 300Hz, 360Hz, etc. The input is from an internally regulated 13.8V power
supply (Tripp Lite PR-10) rated at 7.5A continuous, 10A pulsed. You can see the fundamental at 60Hz and the next two odd
components are about 80-85dB down from 5.657Vp-p (2Vrms), giving
approximately 0.5mV of AC per harmonic. The Superpower output is
consistently below -120dB and largely below -126dB out to 40KHz.
This is under no load, except the Superpower itself. A better test
comes when we pull significant current from the power supply. As you
rectifier voltage ripple increases in direct proportion to delivered DC
Spectrum with 300mA DC load, no pre-regulator, input (red), output (blue)
To show the true abilities of the Superpower, the Tripp Lite cover
removed and the supply voltage was taken directly from the rectified
voltage, before its internal regulator.
The (red) input signal from the filtered unregulated rectifier shows the spectrum of a 120Hz sawtooth wave, typical for a rectifier delivering current. Notice that the regulated output supplying 300mA is virtually unchanged from the unloaded (<10mA) output, with harmonics and noise well below -120dB, roughly 6µV. That's a 100dB improvement!
Note—due to sampling discontinuity, the red input spectrum has numerically generated high frequency content that folds into the passband and gives it a slope. The fundamental at 120Hz and its harmonic peaks above the sloped portion are the signal components of interest.
Spectrum, Input 12.5Vdc+1Vpp ripple (red),
Output 10Vdc out, 300mA DC load (blue)
Above is a spectrum from a fully controlled test, using a regulated 12.5V input source with 1Vpp ripple added at 160Hz. The 10V output signal is at or below -120dB from DC to 20KHz, notice the small spike at 160Hz. Performance was also measured at 60Hz and 333Hz and is just as good. The Superpower regulator is almost as good as the measurement device. This is with a 300mA load and compares favorably with line regulation of a Jung Super Regulator as seen here.
Input=12.5Vdc+1Vpp ripple (bottom),
Output=10Vdc, 300mA load (top)
Here you see the time domain input (bottom) and output (top) of the 12.5Vdc+1Vpp input test. Test frequency is 55Hz, to differentiate from 50 or 60Hz power line frequencies. Both signals are AC coupled to the oscilloscope, which is band limited to 20MHz. The input scale is 1V per division, which was verified with a DVM to be 0.353Vrms, or 1Vpp. The output scale is 2mV per division and is essentially flat at this scale, showing total 20MHz wideband noise. Horizontal scale shows 55Hz.