Metaxas & Sins solitaire, Руководство пользователя

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This is the STATIC performance of a voltage regulator which
although important, does not a
 ect the overall sound of the
ampli fi er as much as the regulator’s DYNAMIC performance
which is in fl uenced by the speed and ‘open loop gain’ of the
regulator.
To understand why the Dynamic performance of a voltage
regulator is so important, we need to go back to our basic
ampli
fi er circuit and investigate what happens to the 1.0 Hz,
10 Volt output signal as it goes across resistor R and
encounters our voltage regulator.
To ensure an absolutely stable D.C. at V+ the residual of the
10 Voltsine wave at the OUTPUT is fed through the
negative feedback loop of the regulator to force the
ampli
fi er to correct this error by applying an inverted signal
identical to the residual sine wave to totally eliminate the
residual sine wave at V+.
A high speed regulator would therefore treat a signal at 1.0
MegaHertz in the same manner as a signal at 1.0kHz. The
ultimate voltage regulator would e
 ectively have a
theoretical output impedance (or ‘Damping Factor’) at V+ of
zero ohms at all frequencies as a result of its wide
bandwidth before the addition of negative feedback.In this
way, the attenuation of the 10 Volts across the resistor R
residual would be complete, and no attenuated component
of the 10 VOLT sine wave could be de
fl ected and return to
the OUTPUT of the circuit and cause severe phase
anomalies by adding to the new signal presented at the
output - remember that it would take a few nanoseconds for
the signal to go through the resistor and come back.
This extraneous out-of-phase information if allowed to adds
to the new OUTPUT signal, would then destroys TIME/
PHASE characteristics of the ampli
fi er circuit. In real world
power supply circuits, the impedance of the power supply
actually increases with frequency because the open loop
gain rolls o
 at high frequencies.