Why should you consider commissioning a custom or semi-custom standard power supply?

On the face of it, a power supply is a basic component. An input, at some value in V AC or V DC, is converted to an output with a different value in V DC. In some applications, it really is that simple. But what if the design or assembly specifications are not completely standard? Which characteristics of an end product design tend to reveal scope for benefiting from a custom or semi-custom PSU?

• The end product requires a power management system, rather than a power conversion system

Some end products operate in volatile, remote or harsh conditions, or are required to maintain constant, fault-free operation for extended periods of time. In these cases, the power supply requires a management system which can provide functions such as: • Performance logging or telemetry • Remote or on-the-fly power configuration • Diagnostics and fault monitoring • Programmable protection features • Connectivity via the internet or other network It is possible to embed these power management functions in the core system, using spare capacity in the host processor or microcontroller. But this adds layers of extra complexity into the host system design. The development time, cost and risk associated with such an implementation are rarely worth bearing. It is normally simpler, quicker and less risky to implement the required functions in a custom intelligent power supply which is optimised for the operating environment and architecture of the host system.

• The end product has a long product life cycle

When using a standard PSU, the customer is at the mercy of the PSU supplier’s production operations. Long end-product life cycles can extend beyond the PSU supplier’s guaranteed minimum support period, leaving the customer exposed to the risk of obsolescence. When it provides a custom or semi-custom power supply, Stadium Power is the original design authority, owning the unit’s design files and bill of materials. This means that Stadium Power can specify replacement parts and maintain alternative sources of supply of components at risk of obsolescence.

• Production and supply-chain risk must be eliminated

The same benefit applies to production risk as to risk of obsolescence. After natural disasters occurred in Asia in 2011, a number of electronic component manufacturers suffered lengthy periods of downtime at their plants, resulting in a severe shortage of materials worldwide and pushing lead times to more than 20 weeks for many components. As the original design authority of custom products, Stadium Power can quickly specify alternative parts to ensure minimal disruption to customers and to provide full continuity of supply.

• Lifetime cost must be kept to a minimum

A standard Commercial Off-The-Shelf (COTS) power supply unit will normally have a lower initial cost (unit cost plus nonrecurring engineering cost) than a custom power supply. But in many cases this does not mean the COTS unit offers a lower lifetime cost. A custom design can be optimised for the OEM’s assembly and production processes. In collaboration with Future Power Solutions, inventory of a custom unit can be managed to support a customer’s lean and just-in-time manufacturing model. And design and development costs that would have been incurred by the OEM to integrate a compromised standard power supply design may be reduced or eliminated when an optimised custom unit is dropped in to a host system design. All these factors affect the lifetime cost equation, and often swing the balance in favour of a custom or semi-custom unit.

Asking the right questions at the start of a design

So what is the right process for deciding whether to use a standard or custom PSU? It is common to start specifying a power system by reference to the required input and output values.

A better place to start, though, is to ask:

• What does the power supply design need to achieve? • What are the design, production and cost constraints affecting the complete system?

 If the answers indicate that a standard power supply is not the right choice, Future Power Solutions and Stadium Power together have the experience and expertise required to implement a successful custom or semi-custom product.  Stontronics specialise in the manufacture and supply of standard, semi-custom and customised power supplies; including AC-DC adapters, DC-DC converters, LED drivers, transformers and other associated power products. Whether you are looking to customise a stock item to better fit your branding or you are looking for an entirely bespoke power unit our engineers in the UK and China will assist you every step of the way from concept to design and finally production. We can offer small to medium scale manufacturing in our 20,000sq ft. facility in Reading, UK with flexible production lines capable of producing a wide variety of power supplies, cable assemblies and transformer manufacture as well as extensive electrical testing.

Stadium Power has been designing and manufacturing specialist power supplies for original equipment manufacturers (OEMs) to international approvals for over 30 years, offering semi-custom variants of standard designs, bespoke designs as well as complete PCBAs and full box build solutions. Our team of specialist engineers will work with you to develop a custom power supply that fully meets your electrical, mechanical, safety, EMC, and thermal management requirements, to deliver a competitive solution with fast time to market. Our R&D centre in Norwich features a 1,000sq ft. laboratory, for the design, prototyping and testing of power products to help drive innovation and technological developments in efficiency, user experience, connectivity and miniaturisation.