Shane Callanan, Excelsys Technologies
As engineering teams are continuously being pushed to deliver leading edge designs in much reduced time frames, they must now look every possible advantage in order to meet these aggressive requirements. One such way to achieve this is to reduce the internal testing of any new components being used. Procurement specialists are also feeling the pinch in trying to incorporate leading edge technology solutions while at the same time ensuring that the premium for this is kept to a minimum.
Nowhere is this challenge more amplified than in the selection of a suitable power supply. Although often seen as a low priority in the design cycle, if the power supply of choice is not fit for purpose, your application will simply not function as required. Having to retrofit a solution mid design can be time consuming and costly, and from a mechanical point of view can often mean a redesign of the casing to accommodate a new design. The result can be catastrophic to a project schedule, as well as the cost structure, and the result may be a single source solution. Avoidance of this is a must.
So in order for the engineering team to satisfy themselves that any given power supply will behave as intended, best practices demand a time consuming and extensive testing of the power supply in the application. The cost of this is often borne internally, but is a necessary requirement. This process will also need to be repeated for each new project, and time used up becomes accumulative. Unless there is overlap in the solutions, very little (if any) of the previous testing can be used for the next generation of the designs. Despite the fact that there may be significant overlap in the type of testing being carried out, there will be very little opportunity to reduce design cycle time.
The solution is instead move to a platform-based approach. We are seeing this more and more in the various industry sectors that we design for (see Figure 1). With this mindset you attempt to develop a series of power platforms that can be used across a range of applications. Power solutions should be scalable and easy to use across a range of applications within your engineering teams. Core technologies across designs often have an underlying basic requirement that either need increasing in power, or a slight change in auxiliary voltages for ancillary devices. The use of a common platform would make for more viable and useable solutions and could significantly reduce the testing required in order to approve any given part. However, this is not without its challenges and due consideration. The underlying question remains; how can all permutations of your power needs be quantified and resolved by a small number of designs?
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Figure 1: A modular power system can address many application areas
The answer lies in a very creative approach, which is incorporated into the parts that we design at Excelsys. We make our solution modular and configurable. In doing so we can provide the user with a solution of building blocks that allows any configuration to be put together in order to meet any requirement.
Let’s look at the possibilities available to the user with just a small number of building blocks.
· Two front end chassis, 600 Watt and 1200 Watts respectively.
· The 600-Watt chassis can accommodate up to 4 cards.
· The 1200-Watt can accommodate up to six cards.
· 11 cards, each one designed to cover a specific voltage range form 1V to 58 Volts.
· Paralleling capability of cards to increase overall load current.
· Series capability to increase overall voltage levels.
· A design that provides access to the end use to modify the voltage in 5mV steps.
· Accessible Internal switches to set the polarity of turn on (active high or active low)
· Internal reference points for current limit and voltage setting are also accessible to set both the current limit set points and voltage set point.
· Enabling and disabling capability of individual or all outputs simultaneously.
We can calculate the permutations with the above being somewhere in the region of 1.8 million different power supply solutions, and all of this achievable with just 13 parts! With the same basic design we can either power an MRI scanner or a waver fabrication tester, or even a water purification system. The real strength in this approach is the ability to make your platforms scalable. The benefits to this are easily quantifiable to both the commercial based and engineering based communities.
Commercial benefits to a modular approach
· Eliminate non reoccurring engineering costs associated with the project
· Reduce the number of power supply vendors
· Consolidation of parts
· Shorter lead times
· Stronger purchasing strategies as you will now be dealing with a much smaller number of suppliers for all of your power needs.
· Scalable solutions
Engineering benefits to a modular approach
· Platform based approach for power architectural requirements.
· EMI remains consistent even as power needs change.
· Synchronization of switching frequencies to eliminate beat frequencies means smaller filters required to meet EMI requirements.
· If power needs change during the project then with a modular approach power supplies can be tweaked to meet the new requirements.
· Proven platform will reduce testing with your application.
· Approvals time reduced, as safety test agencies will become familiar with the parts being used.
· Can be modified at any stage of the project, and no technical impact on UL approvals.
· Parts received as samples are a true reflective of what will be received during volume shipments.
Of course the success of the above platform approach will rely heavily on your selection process and ensuring you are dealing with the right companies to provide these solutions for you. You should also ensure that your final list of companies also has the means to support you on a day-to-day basis from a technical point of view. This will require a team of professional engineers who understand fully your needs and can assist you at all stages of your project requirements. Their ability to support you should be from concept, right through to UL approvals and volume production.
Excelsys Technologies have invested heavily on research, design, and just as importantly an infrastructure to support this very activity. The recent release of the UltiMod series provides two mechanical footprints and 11 interchangeable power cards to can build a solution with a particular emphasis on the 400 Watt to 1200 Watt range.