PSU4SA is a complete power supply unit with many features.
It provides power for DCN23 and a number of PA1CC or PA3CC or other high quality amplifier modules.
PSU4SA has separate linear regulated voltages of 3.3V, 5V and +/-9V to supply the DCN23.
An input sensing circuit keeps an eye on signal inputs at DCN23 to auto start the power amplifiers.
A switch selects between ON - STAND BY - AUTO SENSING to ease the use in daily life. If on or signal is
present this switches the transformer relay on. The transformer ramps up the 4 pieces low ESR capacitor bank
by soft start circuit limiting inrush current to about 7A. When ready, the power amplifiers are unmuted by
pullup to GND. There are two LEDs to indicate STAND BY or ON. PSU4SA will ensure enough resources for
the power amplifier modules to easily drive, even difficult speaker impedances.
The PSU4SA has been revised. It now features a small mains filter on the low power section of the supply, which enhances
both sound and function. The regulation of the lower voltage supplies is now performed by LDO (Low Drop Out) SMT devices and
the supply voltage for the OP-AMPs has been changed to +/-9V for better adaptation of the DCN23. Pads have been added on the
ON and StandBy LED traces to ease assembly when LEDs are not mounted directly on the board. To ease the adjustment of the softstart circuit
for different transformer voltages, two resistor are now leaded versions and easy accessible.
