Amazing load regulation thanks to fast response time and low output
impedance
A perfect regulator maintains a
horizontal line of voltage versus time, no matter what kind of load
transients occur.
The only way to do that is with very fast loop response and very low
output impedance. Superpower has an error amplifier operating at
90MHz bandwidth and an output impedance of single milliΩs.
The best way to illustrate output impedance is with a current step as seen here...
Load Regulation, 1
amp pulse (bottom), output step response (top)
The lower trace in the above oscillogram shows a 50mA to 1 Ampere load current step, 0.1V across 0.1Ω, that steps and settles in less than 5µsec. The upper trace is the transient response of the output voltage; at 20mV per division you see about 8mV DC shift. At 1A this represents 8mΩ of resistance in the measurement path. The transient for both the positive and negative going edges recovers in about 5µsec.
The measurement was done using a high speed (300MHz) pull-down transistor through a 0.1Ω power resistor to regulator Vout. A 100uF electrolytic capacitor was used on Vout to prevent ringing.
This is an extremely demanding test, something required by digital
circuits, so Superpower is a great regulator for DAC and ADC clocks.
For circuits such as audio or microphone preamps, this
performance is far beyond what is normally required. It's also beyond the
performance of other regulators, as you can see in our dynamic performance
comparison page.