Diode companies maintain through-hole segment but at steadily falling output

Suppliers focus on applications with no space requirements. They highlight mature technology and price advantage.

The trend for SMDs is eroding the production share of conventional components such as through-hole diodes in China, the global manufacturing hub for the category. Suppliers there offer them to fill remaining requirement in the computer, communications and consumer electronics sectors, and emerging new energy and smart grid industries. They are taking advantage of outstanding demand in automotive electronics, home appliances, lighting, and medical and industrial equipment as well.

At present, the conventional type makes up about 40 percent of diode yield, with output value representing less than 5 percent of the local discrete semiconductor segment. The last posted nearly 9 percent rise in yield from January to November 2014, hitting 488.32 billion units.

Through-hole units will account for 40 percent of Rugao Dachang Electronics Co. Ltd's turnout by end-2015 from 50 percent. Shenzhen Luguang Electronic Technology Co. Ltd is likewise lowering the allocation to 30 percent from 40 percent.

Even so, the mature category will coexist with SMDs in coming years, owing to its low price and traditional applications. Some manufacturers remain optimistic about the line. Rugao Dachang has released through-hole models, which perform rectification of high-voltage power supplies of magnetrons in microwave ovens and other uses. The diodes have 12kV repetitive peak reverse voltage. Jinan Gude Electronic Device Co. Ltd looks forward to 10 percent higher revenue this year.

As a result of international emphasis on SMDs, China's production of through-hole diodes now exceeds 60 percent of the worldwide total. No output expansion, however, is forthcoming in the years ahead.

There about 200 suppliers in China, all offering the latter. They gather mainly in the Pearl River and Yangtze River Delta regions, and the Bohai Bay Rim Economic Region. The key locations are the provinces of Guangdong and Jiangsu, which generate about 60 percent of the country's aggregate diode yield.

China is the largest production base of discrete semiconductor components, responsible for about half of global output. It is also the biggest market, with a share surpassing more than 50 percent and attracting major players to set up factories there. They include Renesas, ROHM, KEC and Panasonic.

SMD expansion

SMD diodes' widening market is fueled by miniaturization in many downstream applications. In addition to this, the components are increasingly used because they are easy to assemble, improving manufacturing efficiency and reducing cost pressure.

As such, key industry players are intensifying development work, one aspect of which focuses on the substrate material. Cree, Infineon, STMicroelectronics and ROHM have switched to SiC from silicon and introduced compliant variants. The former input boasts wider band gap, larger critical electric field and higher thermal conductivity, enabling SiC devices to operate at elevated temperatures and voltages.

In China, only a few companies have achieved similar breakthroughs. They include Global Power, which churns out SiC Schotty diodes in 600V to 3.3kV.

The worldwide market for SiC products is expected to surge at about 42 percent CAGR from 2014 to 2020, according to MarketsandMarkets.

See a comparison table of diode suppliers on GlobalSources.com