Volume production of fingerprint-recognition and LCD driver chips for the iPhone 5S should have started at the end of June or early in July, but issues related to yield rates will delay commercial production of the two chips to the end of July, therefore affecting the initial supply of the iPhone 5S, the sources explained.
The fingerprint recognition chip was reportedly designed by AuthenTec, a company Apple acquired last July. Issues with its original design caused the lower yield rates, say the site's sources. Production of the chips has been outsourced to TSMC and packaging is done by Xintec.
The poor yield rates are said to delay the supply of about three million iPhone 5S units to the fourth quarter. Apple is reportedly planning to ship a combined 30 million units of the iPhone 4, iPhone 4S, iPhone 5, and iPhone 5S in Q4, 2013.