750W AC/DC Reference Design

The reference design demonstrates peak present management in a ZVS Full-Bridge topology with digital slope compensation for effectivity and lowered software program overhead.

The ability electronics business more and more calls for increased effectivity, reliability, and energy density. This demand has spurred the fast enlargement of digital energy options, significantly within the telecommunications and server energy sectors. Digital management of energy provides has been a broadly mentioned and debated matter for years. The mixing of subtle peripherals for energy provide administration into microcontrollers and the appearance of superior high-speed units within the semiconductor business has facilitated higher adoption of digital energy applied sciences. Strategies beforehand dominated by analogue options at the moment are achievable with digital strategies. In mild of those developments, the reference design from Microchip demonstrates the appliance of peak present management inside a ZVS Full-Bridge topology, using a totally digital slope compensation approach that minimizes software program overhead.

The 750W AC-DC Reference Design incorporates a semi-bridgeless PFC topology adopted by a peak present managed zero-voltage switching full-bridge (ZVS FB) converter with digital slope compensation for very excessive conversion efficiencies. This energy provide helps firmware updates, together with the compensator algorithm, with zero downtime to the system it powers whereas operational. It makes use of two dsPIC33EP “GS” digital-power DSCs for full digital management of the facility conversion and all system administration features.

The ZVS FB Converter is engineered to cut back an enter DC voltage of 400V to an output DC voltage of 12V. A particular side of the reference design is its implementation of peak present management by means of a totally software-based slope compensation algorithm, which prevents the necessity for exterior analogue parts for slope compensation. The design is obtainable royalty-free below the phrases of the licensing settlement.

The design boasts full digital management and a standardized 1U type issue, that includes a 20 ms minimal hold-up time to compensate for drop-outs throughout UPS step-in. It contains each below/overvoltage lock-out and adaptive management. A peak current-controlled ZVS Full-Bridge Converter makes use of distinctive adaptive digital slope compensation software program. Moreover, the system demonstrates the aptitude for on-line firmware updates (Stay Replace) on each the PFC and DC-DC converter phases, enhancing performance and efficiency with out downtime.

The ZVS FB Converter is also used in server and telecom energy provides, battery chargers, and renewable power purposes, primarily as a consequence of its high-efficiency operation and easy management mechanisms. Usually, this topology employs both Common Present mode management or Voltage mode management, necessitating a capacitor in sequence with the transformer to avert flux strolling.

Nonetheless, the implementation of peak present management eliminates the necessity for the sequence capacitor by means of dynamic flux balancing. This strategy addresses subharmonic oscillations, widespread in obligation cycles over 50%, by integrating a slope compensation ramp that’s both added to the inductor present or subtracted from the height present reference produced by the voltage loop compensator. Peak present management, primarily an analogue approach, is applied utilizing parts reminiscent of linear amplifiers, transistors, RC networks, analogue comparators, or by means of devoted Software-Particular Built-in Circuits (ASICs).

Microchip has examined this reference design. It comes with a invoice of supplies (BOM), schematics, meeting drawing, printed circuit board (PCB) format, and extra. The corporate’s web site has further information concerning the reference design. To learn extra about this reference design, click on right here.