Tegra 4 was supposed to be production ready in Q4 2012 and the general expectation was that CES 2013 would be marked by the launch of phones and tablets based on the new chipset.

It turns out that the chip needed another re-spin, something that usually creates a delay of roughly a quarter. We don’t know which part of the chip was to blame but our sources claim that Tegra 4 is a complex chip with a lot of components where many things can go wrong.

Nvidia dared to move to 28nm, change the core from A9 to A15 and find a way to make its LTE work. There were a lot of things that could go wrong and obviously some did.

This is why Intel first shrinks the core, for example from 32nm to 22nm, and then in its “tock” cycle goes for a newly designed core. Nvidia doesn’t have that luxury, as making a 28nm version of Tegra 3 would not be enough for the SoC market in 2013.

A few people at Nvidia have been telling us that the chip has been sampled to accounts and Nvidia is planning to have some designs announced at the Mobile World Congress. We managed to confirm this schedule with some Nvidia partners.

We expect to see tablets and phones based on Tegra 4 selling in Q2 2013, of course if all goes well from here.