Apple has reportedly added four Taiwan manufacturers of integrated circuit boards to its iPad 3 supply chain, in order to keep costs low, DigiTimes reported.

Citing anonymous industry sources, DigiTimes reported today that Taiwan's Novatek Microelectronics, Richtek Technology, Capella Microsystems and Integrated Memory Logic have entered the iPad 3 supply chain. However, none of the integrated circuit makers confirmed the reports.

"Apple is now more willing to adopt IC solutions from Taiwan-based IC design houses as it is adjusting the cost structure for iPad tablets in order to compete with an array of tablet PCs to be launched by rivals in the second half of 2011, commented the sources," the report said.

Integrated Memory Logic has reportedly been tapped to supply "gamma Vcom buffer solutions" for Apple's anticipated third-generation iPad. That technology is said to be used in touch panels for smartphones and tablets.

In addition, Novatek will reportedly supply LCD driver integrated circuits, Capella will provide ambient light sensors, and Richtek is said to be building integrated power management integrated circuits.

Recently, various reports claim that a so-called "iPad 2 Plus" could launch this year with a high-resolution display. Supporting those claims, both LG and Samsung are said to be working on low temperature polysilicon 2048 by 1536 pixel displays for Apple's next generation tablet.

Another report, also from DigiTimes, said that Apple's overseas manufacturing partner Foxconn has been in talks to remain the sole assembler of iPad 3 units in 2011.