Motor soft starters

Makers of AC/DC adapters in mainland China are boosting production efficiency and output quality to grab an even bigger piece of the market as demand picks up.

These companies revealed that orders have started to improve since the beginning of the year, jumpstarting production schedules.

Anticipating an economic recovery, many makers are expanding capacity through investment in automatic machinery, abandoning traditional labor-intensive practices. Shenzhen Tenwei Electronics Co. Ltd, for example, allocated $450,000 for a Panasonic SMT line and aging equipment, which once installed are expected to increase capacity by at least 15 percent from the current 1.5 million units monthly. Huntkey Electronics Co. Ltd’s similar investment will raise its efficiency at half the workforce requirement. Others are adding factory space. Shenzhen Flypower Tech Co. Ltd is leasing a nearby 8,000sqm facility.

Makers believe that automation, along with new test equipment, will elevate their product quality levels as well. In addition to the usual standards such as CCC, CE, UL, FC, CB, GS, CQC, SAA and CSA, there are environment-conscious directives, including the Energy Star, Energy-using Products or EuP, WEEE and RoHS. To comply with these requirements and secure more orders, especially from the US and the EU, suppliers are pushing energy-efficient products with safety features and anti-EMI.

China’s selection of AC/DC adapters consists of 3 to 120W models. A few suppliers also offer designs with up to 250W output power. The products have input voltage of 100 to 240VAC or a maximum of 90 to 264VAC and input frequency of 50/60Hz or 47 to 63Hz. Most have overpower, overvoltage, overcurrent, overtemperature and short-circuit protection, and a built-in EMI filter. More units are now equipped with plugs and tips for use with various devices.

Mainland China has been the line’s manufacturing powerhouse for nearly a decade now, having benefited from the global industry’s migration that started in Europe and Japan and moved to Taiwan in the 1990s before crossing the strait. Mainland suppliers currently account for more than 70 percent of world supply, with production exceeding 1.2 billion units in 2008.

The local industry is poised for further growth of about 10 percent annually in the next two or three years.

The development has been driven by demand from the mobile phone, DSL modem, laptop, digital camera, MP3/MP4 player, PDA, game machine, printer, medical equipment and household appliance sectors.

Guangdong, Jiangsu, Zhejiang and Fujian provinces, and Shanghai are the major manufacturing centers for AC/DC adapters. Eighty percent of products come from Shenzhen. The city in Guangdong is home to many large-scale operations, including Huntkey and Kuantech (Shenzhen) Co. Ltd. Large makers have annual revenue exceeding $70 millionand employ more than 3,000 workers. Others have as few as 500 workers and sales starting at $15 million.
More applications targeted
Product safety, quality emphasized
Further price cuts forecast
Emphasis on energy-efficient models
Portable electronics drive line

To expand their reach, makers are looking to release AC/DC adapters for products with high power requirements. Laptops are seen as such an opportunity in 2009, as declining prices stimulate demand in overseas and domestic markets. These are forecast to register 2.8 percent growth, according to the market research and analyst firm IDC.

For this reason, Huntkey plans to increase this application’s production share to 30 percent from last year’s 10, and scale down its mobile phone-use line to 20 percent from 50. Its existing 90W adapter series for laptops features eight tips for compatibility with major brands. A 5V USB port enables charging of portable devices, including mobile phones, DVD players, digital cameras, PDAs and MP3/MP4 players. The input plug complies with the IEC320-C6, IEC320-C8 and IEC320-C14 specifications.

The adapter meets CCC, UL, VDE, BS and SAA standards.

Shenzhen Tenwei plans to enter the RFID field, targeting printers and tags. For now, the maker is considering a telecom project with the India government and LG of South Korea, which if pushed will double its exports. Shenzhen Nalin Elec. Tech Co. Ltd is optimistic about the money counter sector, noting large orders since end-2008. Shenzhen Flypower will shift focus from PC to telecom AC/DC adapters.

China makers allocate 3 to 10 percent of sales to product development.

	Mainland China's Shenzhen Tenwei offers model TA09-01903420, a 12V adapter with UL, CE, TÜV/GS and CB approval

Safety and quality remain product development objectives for the line, with improvements emphasizing greater efficiency, reliability, power density and anti-EMI. Pulse width modulation is among the technologies being adopted to enhance product performance. Others that are widely used in AC/DC adapters above 75W are pulse frequency modulation, burst-mode and resonant half-bridge soft switching.

Generally, makers conduct chip selection, transformer design and manufacturing, solution selection and optimization, and QC. Tests cover EMC, EMI, intercircuit, function and aging.

Large operations have more-advanced testing equipment and processes. Huntkey, a major computer switching power supply maker, adopts thermal simulation to optimize product designing, and subjects prototypes to highly accelerated life testing and highly accelerated stress screening. It has long cooperated with authentication companies and testing labs for EMC, CQC, CSC, TUV and SMQ approval. Huntkey also has a safety lab endorsed by TUV-PS. The maker employs a 200-member R&D team, including 40 specialists.

As a further quality guarantee, suppliers source ICs mainly from overseas companies such as On-Bright Electronics, Texas Instruments, ON Semiconductor, Infineon, Fairchild Semiconductor, Intersil and Power Integrations. For low-output ripple and noise, they use capacitors from Japan’s Elna and Nichicon.

	Model SNLB100120W1A from Shenzhen Nalin of mainland China is a 12V adapter that meets various safety standards

Most makers are planning another round of price reductions, not exceeding 5 percent. That comes on the heels of a recent 10 percent cut. Falling material and component costs and stiff competition are the motivators.

AC/DC adapter consists of a shell, power transformer and commutation/voltage-stabilization circuit, components that account for 60 to 80 percent of total production outlay. Plastic costs decreased by about 10 percent and electronic components 5 percent. Copper dropped 50 percent, but the effect on product prices was minimal because it accounts for only 5 percent of the materials.

Cost reduction is a big part of suppliers’ strategies for staying buoyant. Shenzhen Nalin plans to develop 90 to 110V AC/DC adapters, which cost 20 percent less to make than the conventional 90 to 264V models. The products will target countries using 110VAC electricity, diversifying the company’s markets.

Huntkey is aiming for the long term through standardization and authentication to eliminate the additional expenditure in securing third-party approval.

Interviewed suppliers, however, warn against unscrupulous companies that use recycled ICs and plastic shells to bring down costs and offer much lower prices.

A/C adapters with 5 to 24W output power, 3.3 to 24V output voltage, 0.5 percent output voltage tolerance and 65 to 77 percent power efficiency are quoted from $1.50 to $3.50. These bear CE, UL and CCC approval.

For 24 to 65W models, prices range from $3.50 to $12. The other specifications are 5 to 24V output voltage, 5 percent output voltage tolerance and 77 to 85 percent power efficiency. The products in this segment have CE, CB, TUV, GS, UL, CCC, TLC, E-Mark, PSB and FCC approval.

Units with 65 to 120W output power are more than $12. The output voltage is 12 to 24V, output voltage tolerance 5 percent and power efficiency 83 to 90 percent. These adapters carry CE, CB, TÜV, GS, UL, CCC, TLC, E-Mark, PSB and FCC certification.

All of these products have 100 to 240V input voltage and 50/60Hz input frequency.

Makers adjust export prices to fluctuations in foreign exchange, or quote in a stable currency.

With energy conservation becoming a major concern, many of the latest AC/DC adapters from Hong Kong suppliers, including Click Technology and Minwa Electronics Co. Ltd, have increased efficiency ratings compliant with CEC Level IV or V specifications.

In addition, products are certified to various international standards, including WEEE, RoHS, GS, UL, cUL, CE, C-Tick, PSE, SA, SAA, JIS, BSI, Semko, Nemko, Demko and EK, qualifying them for export worldwide.

Commitment to the environment is also reflected in manufacturing and management processes. Some suppliers have GMPS and SA 8000 certification.

Hong Kong has more than 40 makers, with products ranging from low-cost, entry-level unregulated models to midrange and high-end high-efficiency, switch-mode power supply (SMPS) units. Most also provide related products such as power supplies, transformers and chargers.

Portable electronic devices have been the main driver of the line’s export growth in recent years. In the past 18 months, however, netbooks have emerged as a major focus of attention based on the number of new models targeting this application. Some recent releases have even taken on matching compact designs such as Click’s 90 and 48W adapters. The company said the 48W model is about one-third the size of adapters bundled with popular netbook brands. It has also released 12 and 24W series with 5 to 24VDC, 2.4/4A output.

At Minwa, one of the latest AC/DC adapters, the MW 2108, is a 90W SMPS for laptops. It supports 100 to 240VAC 60/50Hz input and 15, 16, 18, 19, 20, 22 and 24VDC 4.5A output. The unit comes with a 6MC output plug. Another new model from Minwa is the MW 3NU10GS SMPS with USB outlet. It has 100 to 240VAC 60/50Hz input and 5VDC 1A output.

The multiplug configuration adopted in new universal travel chargers featuring plugs that can be connected and disconnected from the main housing is also a design trend in Hong Kong. A variation embeds retractable plugs into the housing for single-unit portability.

Taiwan suppliers of AC/DC adapters continue to emphasize compact and lightweight form factors, steady power performance and safety features in product development.

These design trends target applications in portable electronics such as mobile phones, laptops, portable media players, DVD players and music devices.

An example is the 5W model from ENG Electric Co. Ltd that has a universal AC input range of 90 to 264VAC, low ripple noise feature and no minimum load requirement. The model weighs 72g.

ENG sources materials from the US, Europe and Japan. The company employs 65 QC engineers under efforts to ensure a 99.5 percent product acceptance rate and compliance with UL, CSA, VDE, IEC, SAA and JET standards.

Part of Taiwan’s healthy power industry, AC/DC adapters have the support of more than a hundred makers and are among the island’s three major lines in the sector, the other two being switching power supplies and UPS. Among the major suppliers are AcBel Polytech, Delta Electronics, ENG, the FSP Group, Lite-On Technology, Mean Well Enterprises, the Topower Group and Zippy Technology.