sine amplitude converter (power supply) (SAC)

Sine Amplitude Converters(SAC) are DC-DC converters. They are used in power supplies for boards and systems and have an efficiency of about 98%, which is far higher than converters that operate with square-wave signals.

Due to the increasing sensitivity in terms of energy savings, the improvement of efficiency plays an important role, especially since a lot of energy can be saved in the supply of boards and systems. This is also the case with the signal shape of the DC-DC converter, because sinusoidal signals have fewer harmonics than square-wave signals, which results in a significant reduction of the interference voltage component.

SAC converters work according to the resonance principle - the two transformer sides form the resonant circuits - and switch the sinusoidal signal in zero crossing, Zero Current Switching (ZCS) or Zero Voltage Switching( ZVS). Zero-crossing switching reduces passband losses and increases power density, thus increasing efficiency. SAC converters can operate at frequencies of 1 MHz and higher, which helps further improve efficiency, power density and reduce costs. The load dependence of SAC converters is expressed in terms of amplitude. As the output load increases, the primary voltage of the transformer increases, and at low load, the amplitude decreases to zero when no current is drawn from the secondary side.

Sine-amplitude converters are used, among other things, in Intermediate Bus Architectures( IBA), where they generate the various low voltages for supplying the boards.