What’s all this stuff about "Digital Power"?

Posted on

Evidently each 2-3 weeks an article or news announcement about “Digital Energy” seems in digital design periodicals or online news hyperlinks. Actually, one business publication appears to be having a love affair with digital power, because it mentions it in simply about each subject.

So what's all this fuss about Digital Energy and what's it anyway? Nicely, the easy reply is that there are two fundamental kinds of digital power. These are Digital Management (used internal to the power gadgets) and Digital Energy Administration (gives external management and communications between power gadgets and a grasp controller).

Digital Management
Nearly all of switchmode AC-DC and DC-DC power provides/converters use analog strategies to control/management the output voltage, present, and power issue correction circuits, and so forth. The closest that the majority of those gadgets come to wanting a bit digital (On/Off states) in nature is by using Pulse Width Modulation (PWM) of their switching regulator circuits; however even that could be a little bit of a stretch.

In recent times, new built-in circuits (ICs) have been developed that may exchange “analog” management ICs and discrete circuits, that are used extensively in all power gadgets, with these which are, at the least partly, “digital” in nature. These internal ICs and circuits carry out such management features as: voltage regulation (VR), power issue correction (PFC), pulse width modulation (PWM) management, internal monitoring/alarms, and external communications.

The benefit of those digital ICs is that they are often programmed by engineers with digital or analog electronics coaching. And, because the Universities are pumping out extra digital (e.g., laptop science) than analog engineers today, these digital ICs have gotten engaging. Nevertheless, at current the price of these digital ICs (together with NRE for the tools wanted to program the gadgets) continues to be greater than for the mature analog ICs. Nonetheless, some predict that these IC prices will turn out to be equal inside the subsequent 12 months or so. A possible drawback of those digital ICs is that, by their nature, they require a high velocity clock to function, which may add to the radiated and carried out noise coming from the power provide or converter. Nevertheless, superior features akin to fault diagnostics/prevention and improved power efficiencies are among the many guarantees of the new digital management ICs.

Digital Energy Administration
As talked about above, Digital Energy Administration (DPM) entails the external management and communications between power provides (or converters) and a grasp controller. At present, many analog-based power options have already got the flexibility to speak with an external laptop or controller through digital communications hyperlinks (e.g., RS232, RS485, GPIB, or I2C bus).

Newer DPM management and communications codecs have developed which are designed to function with the new digitally-controlled power gadgets. These embrace DPM applied sciences akin to PMBus (Energy Administration Bus) and Z-One. Sadly, these applied sciences are usually not suitable or interchangeable. Actually, at present there are lawsuits between the backers of each of those applied sciences.

If I have been a possible consumer of those Digital Energy Administration schemes, I'd keep away from them till the lawsuits are settled (anticipated to happen inside the subsequent 12 months), quite than discover out later that the price of these DPM ICs or controllers have considerably elevated as a result of royalties that should now be paid to the corporate that gained the lawsuit.

The potential benefits of the DPM and digital power applied sciences basically, embrace enhanced bidirectional communications, fault diagnostics, distant programming of the linked power provides/converters, computerized compensation of dynamic enter and output load modifications, and general enhancements in efficiencies that relate to green-power.

In Abstract
Though “Digital Energy” is a well-liked buzzword today, particularly by these corporations who've developed or adopted the applied sciences, the underside line will at all times be: “What do I get for my cash?” At current, there are hardly any power provide or converter functions that “should have” digital power when in comparison with the numerous decrease price and field-proven analog options that exist.

For instance, throughout their new power-product design and growth course of, Lambda has designed in-parallel gadgets that employed each analog together with people who use digital management ICs and applied sciences. In all circumstances, the ultimate determination on which expertise finally goes into manufacturing has been primarily based on comparative price/efficiency elements; which is the dominant determination issue for his or her clients.

When the time comes that digital power merchandise provide the identical or higher efficiency and reliability, together with the ”wanted features”, on the similar or decrease price as analog-based merchandise, that's when Digital Energy will turn out to be the profitable expertise. Realistically, sometime digital power will present a price/efficiency benefit over purely analog power gadgets. Who is aware of for positive when that point will come.