One thing I'm wondering about why didn't the ipv4 use the 350J chip. Too expensive.
I am sure that is it.
Also, the SX330 chipset is designed differently in terms of how it does battery charging. It can handle a 2 amp current supply via a DC connector to charge the batteries.
So my guess is that cost and customer specifications are both relevant factors. Also, the features missing in the SX330 compared to the SX350J (e.g., modes, gravity sensor) may not be something that YiHi is willing to include on a customer's chipset at the moment.