Simplify Global-Ready Device Design with Versatile AC/DC Power Supplies

Electronic equipment is often intended for use in multiple countries, creating global configuration challenges for designers of systems for information and communications technology (ICT), medical devices, industrial equipment, and home appliances. Due to widely varying regulatory environments, achieving global compliance is particularly complex, costly, and time-consuming, delaying releases and compromising competitiveness.

This article briefly discusses the compliance challenges designers face when developing global products. It then introduces robust, versatile desktop power supplies from GlobTek and shows how designers can use them to meet international compliance requirements and simplify product design, certification, and deployment.

The differences in mains electricity around the globe

Globally, AC power mains use 15 different wall socket types, each designed to comply with local standards and safety regulations. The variety reflects the fundamental differences in supply voltage and frequency, which can be broadly grouped into four main schemes: 220 V to 240 V at 50 Hz, 220 V to 240 V at 60 Hz, 100 V to 127 V at 60 Hz, and 100 V to 127 V at 50 Hz (Figure 1).

Figure 1: Power mains voltage and frequency vary globally, with four main schemes in use. (Image source: DigiKey)

The reason for these differences is mainly historical, the result of political and trade alliances as grids were rolled out, as well as concerns regarding safety, long-distance transmission efficiency, and lighting and motor performance. Nonetheless, it falls to designers to determine the best way to convert mains electricity to power their products, while navigating compliance challenges that can lead to staggered rollouts and costly delays for global product releases.

How external power supplies simplify product power design

Typically, mains-powered equipment comes with an internal power supply that converts mains electricity directly from a wall socket via a hardwired power cord or separable IEC cable. For products operating in a single region, this provides several advantages, including optimized power conversion and high integration, resulting in clean designs with minimal clutter.

The problem with this integration is that it locks a product into serving a limited number of regions. With internal power supplies, manufacturers need different SKUs to sell the same core product globally, which increases costs and complicates development and deployment.

Alternatively, external power supplies decouple a product’s internal power design from the mains supply, simplifying internal power circuitry and enabling compact product form factors. As a result, manufacturers can create a single product SKU with a unified design that meets international requirements. By unifying power design across different product ranges, a single power supply can serve multiple devices, easing regional stocking logistics. For these reasons, many designers choose external power supplies when developing products for global markets.

Robust, adaptable power supplies for global product distribution

The Globtek GTM96600 series of power supplies is a versatile external power solution that supports many products across diverse use cases and geographies. This series of AC/DC desktop power supplies supports a wide AC input range of 100 V to 240 V at 50 Hz to 60 Hz, with a fixed DC output of 5 V to 54 V in 0.1 V increments. The robust and reliable GlobTek adapter design offers the following performance benefits:

• Up to 60 W output for a wide range of applications
• High average efficiency and ultra-low no-load consumption to reduce standby energy usage with Level VI energy efficiency standards compliance
• Operation in up to +74°C with derated output and cold starts down to -40°C for use in harsh industrial conditions
• Class I and Class II options that enable enhanced safety in medical and consumer settings

Alongside these electrical specifications, the GTM96600 series offers an innovative mechanical design with interchangeable blades that support local AC wall sockets for different regions. Two blade examples are the R-NA-2(R) (Figure 2, left) option for Class II North American and Japanese markets, and the R-EU-3(R) (Figure 2, right) option for Class I supplies in Europe and South America.

Figure 2: GlobTek’s interchangeable blades, such as the R-NA-2(R) (left) and R-EU-3(R) (right), enable GTM96600 adapters to fit sockets directly in multiple regions. (Image source: GlobTek, modified by author)

Additional blade options are available to support wall sockets in Australia, China, the United Kingdom, Hong Kong, and Singapore. For other regions or longer cable runs where wall sockets may be farther from the equipment, GlobTek provides a wide range of standard detachable IEC 60320 power cords that integrate seamlessly with the GTM96600 series onboard connectors.

GlobTek interchangeable blades and power cords are supplied separately, allowing device manufacturers to adapt orders to each region by simply shipping with the local blade or cord accessory package, easing inventory management. In addition, the GTM96600 series includes a barrel plug kit for connection flexibility at the DC output. The standard kit includes three straight male barrel plugs with widely used inner diameters of 1.3 mm, 2.1 mm, and 2.5 mm. Polarity is determined by the orientation of the tip relative to the main power supply. Alternative connectors are available separately.

The GTM96600 series offers comprehensive certifications and safety compliance to shorten time-to-market, with global approvals in Korea, Taiwan, India, and more. These standards include:

• IEC 60601-1 (medical)
• IEC 62368-1 (ICT and audio-visual (AV))
• IEC 61558-1 and UL 1310 (power supply units (PSUs))
• IEC 60335 (household appliances)

Exploring the GTM96600 series AC/DC desktop power supplies

The GTM96600 series encompasses many DC output options, ranging from standard to relatively niche. A prime example of an adapter suitable for widespread use is the RR9LE5000T00CIMR6B (Figure 3), which includes a barrel connector kit.

Figure 3: The RR9LE5000T00CIMR6B Class I supply comes with a barrel connector kit and provides a flexible solution for 12 V at 60 W, typical of global ICT products. (Image source: GlobTek)

This Class I supply offers the full safety benefits of three mains pins, with an internal connection to ground for fixed or metal-cased equipment. The 12 V output at 60 W supports many applications, such as network routers, external hard drives, and mini PCs, as well as home audio equipment and LED lighting systems, which are likely to require the maximum current capability of 5 A.

Like most of the GTM96600 series, the RR9LE5000T00CIMR6B measures only 117.5 mm × 53.5 mm × 36.6 mm for minimal intrusiveness. The cord length is 1.20 m, which is representative of the range but varies by unit.

For a slightly less common 30 V output, the RR9KR2000T00CIMR6B (Figure 4) provides a Class II adapter with a two-pin (ungrounded) input for devices where a building’s ground connection may not be reliable. The adapter accepts either a C8 IEC cord or an interchangeable blade.

Figure 4: For 30 V systems where reliable mains grounding cannot be guaranteed, the RR9KR2000T00CIMR6B simplifies safe power delivery. (Image source: GlobTek)

Retaining the full 60 W output, the RR9KR2000T00CIMR6B serves less common products, such as motorized dental instruments and specialized industrial control systems where 2 A is sufficient. It also provides a solution for larger Li-ion battery charging applications, such as power tools.

Finally, the RR9LB6667T00CIMR6B (Figure 5) is an example of a supply with a specialized 5.95 V output. This 40 W Class I adapter pairs well with proprietary charging systems configured slightly above the typical 5 V output. In addition, the relatively high current capability supports portable medical equipment, such as home healthcare monitors and ultrasound devices, that require low-voltage operation for safety reasons.

Figure 5: The RR9LB6667T00CIMR6B provides a solution for non-standard, low-voltage power delivery where a ground pin is essential for device safety. (Image source: GlobTek)

Conclusion

For designers of global products, the numerous mains voltage standards can significantly complicate product design, certification, and deployment. The versatile GlobTek GTM96600 series solves these issues by breaking the link between a product’s internal power delivery and geography, providing a robust, certified power supply for global applications where safe, reliable power delivery is essential.