Chip vendors including Qualcomm, Broadcom, STMicroelectronics, NXP, Texas Instruments (TI) and OmniVision reportedly have started stocking their solutions used for Apple's next-generation iPhone slated to hit the market in the second half of 2012, according to industry sources.

Qualcomm and Broadcom are producing 4G and Wi-Fi chips using a 28nm process at Taiwan Semiconductor Manufacturing Company (TSMC), indicated the sources, adding that OmniVision is currently also seeking capacity at TSMC's 12-inch fab, resulting a tight production capacity for the foundry's 28nm process.

Qualcomm alone needs about 10,000 28nm 12-inch wafers, or one-third of 28nm capacity at TSMC, for the production of 4G chips for iPhones, not mention the additional supply of 4G chips to other clients, revealed the sources.

Nvidia also takes up about 10,000 units of 28nm wafer capacity at TSMC, leaving Broadcom, TI, Altera, Xilinx and other chipmakers to share the remaining 28nm wafers, said the sources, adding that it would be difficult for TSMC to meet market demand for 28nm process until it ramps up its 28nm wafer starts to 50,000 units a month around the fourth quarter of 2012.

Meanwhile, STMicroelectronics is ramping up its output of MEMS devices, while NXP and TI are also building up their inventory of analog ICs for iPhones.

The move by international chipmakers and the tight 28nm capacity at TSMC herald strong sales of IC products in the third quarter of 2012, said the sources.