Hi Chen,
It looks like the primary difference is DDR3L and DDR3U support (lower signaling voltages, lower VDD range) on the SN74SSQEC32882. SN74SSQE32882 only supported standard DDR3.
Hi Mark,
It sounds like you are using SN74SSQE32882. This device was released before JEDEC specified the QuadCS Mirror mode for the SSTE32882 Standard. Therefore the device only supports dual chip select in mirror mode.
I recommend to use our newer…