Why are people even talking about the Bitmain AI chip and this thing?
That chip is optimized for FLOATING POINT operations, like any AI chip - it is NOT going to process INTEGER operations very well like mining requires, NOR is it going to be efficient at doing so.
The BM 1680 is NOT A MINING CHIP and is not going to offer decent performance per $ or watt since the bulk of the chip would go to waste AND WASTE SOME POWER if someone tried to mine on it.
Could be not the same chip but something very similar, if you look at the block diagram it resembles very closely GPU without texturing and rasterization units(you dont need these for mining) and pcie bus is moved to an fpga chip. They just have to substitute these "NP" units with something more appropriate for mining.