IC component orders coming from China's smartphone market have risen substantially, according to sources in the supply chain, which estimated that monthly demand for smartphones sold in China has climbed to 25 million units from about 20 million in the fourth quarter of 2012.

Smartphone demand in China is set to top 30 million units monthly in March and April, as companies gear up for the May 1 holiday season, the sources indicated.

A pull-in of orders for smartphones has helped clear the previous inventory pile-ups in the IC supply chain, and even caused tight supplies of some components, such as high-megapixel camera modules, the sources said.

China's first-tier handset vendors including Huawei, ZTE, Lenovo and Coolpad are expected to see their handset shipments double from a year ago in the first quarter of 2013, buoyed by the continued expansion of the region's smartphone market, the sources noted.

MediaTek has responded to the sources saying that the China smartphone industry supply chain has encountered shortages of several components, mainly those for high-end models. For instance, the supply of 10-megapixel camera modules has already fallen short of demand, according to MediaTek.

MediaTek added that the current tight supplies of certain components will unlikely affect its IC shipments in the short term.

In other news, MediaTek expects its first-quarter revenues to meet the high end of its guidance given previously. Revenues for March are estimated at NT$9 billion (US$301 million), up 50% sequentially.