SPX has raised the bar on ripple rejection
Once again ripple rejection (PSRR) has been the most difficult to make of all our data sheet measurements. After making a (fourth) measurement fixture because of high frequency feed-through, we have a new set of measurements for a new generation of regulators. To read the full story, see this article on the AudioxPress web site.
Here is what we measured, where higher numbers represent better rejection, thus less ripple that gets to the regulator output:
Keep in mind that 120dBV represents 1µV and 100dBV is 10µV of ripple
at the output.
The test is done as described below using ±0.5V sine wave on top of 15Vdc.
Notice that SPX reduces ripple by 120dBV at 80KHz, unrivaled in the world as far as we know!
Our customers' comments that their systems sound better with Superpower are backed up by measurements—order one to hear for yourself, it really is this good.
To see all the details with spectra, see this page with comparison graphs.
The source fixture uses a DC+AC driver using an op amp servo feeding a low impedance MOSFET to deliver a good sine wave on top of a DC voltage.
We did direct comparison measurements by setting up the fixture,
setting Vin and frequency and plugging in each of the regulators in
turn. Testing was done with no load. A 16 bit 195K sample/second
autoranging A/D was used for the FFT measurements.
Measurements were made from 55Hz to 80kHz. Of course we use our regulators to
power the circuitry to test our regulators!