Apple’s supply chain is not only large, but it’s the primary source of information and leaks regarding future Apple products. Today it came out though a Citigroup analyst that Apple may be talking to Taiwanese chip manufacturer TSMC about a quad-core chip that could power a version of the iPad as soon as 2014. Apple’s worked with TSMC before and has even tried to buy thier services exclusively. However, the current generation A6 is manufactured by Samsung, but it’s rumored that the A7 will be a TSMC product. What’s surprising about this rumor is that the die is 20nm, which is significantly smaller than the current 35nm die used in the third-generation iPad. Smaller dies have significant advantages: they should be faster, more dense, and use less power. Apparently, production of these new chips won’t begin until the second half of 2013.