Cost-effective design of AC/DC converter with programmable power amplification

The paper discusses the cost-effective design of an AC/DC power supply whose output DC voltage is the linear amplification of an input control signal. A monolithic PWM circuit is used as a core of a printed circuits board (PCB) realization using commercially available components. Integrating both AC/DC conversion and power amplification in a single PWM-based scheme has two main advantages: (i) bounds the overall system complexity for applications where conversion plus amplification is required; (ii) reduces internal losses and heat removal/cooling costs due to the high efficiency of the switching approach, higher than 90 %. The behaviour of the proposed scheme as AC/DC converter and amplifier has been carefully verified for several input control values and output loads. The PCB design has been realized considering both 2 KW and 500 W output power target applications. The achieved results in terms of limited PCB size, programmability and stability of the amplification gain, power efficiency and ripple are very interesting when compared to other schemes proposed in literature for low-complex AC/DC conversion targeting the same power range.