Chipworks reverse engineering of Asus Transformer Prime tablet revealed that its primary image sensor is Omnivision's 8MP OmniBSI-2 sensor "with die markings AEQGG6 OV2B8B0 and according to the specifications the device is the OmniVision 8830". Features that show it to be BSI2 include the suspected TSVs located on either side of the bond pads (shown below) and the copper metallization found during SEM analysis.
Thanks to EK for pointing me to this!
i wonder if asus looked at the ov8850 which is a quarter inch optical format using a 1.1um pixel pitch (as opposed to the 8830 which is 1/3.2" w/ 1.4um). if it didn't look at it, why not? was it available for evaluation? if asus did look at the 8850, why did asus chose the 8830? was it a cost consideration, concern about lower sensitivity of the 8850?
ReplyDeletei was hoping for ovt's sake that we'd see their 1.1um product making its debut in this product and am disappointed. i seem to recall that sony's 1.12um has similar sensitivity to it's 1.4um--at least better than ov's 1.4um v. 1.1um. does it appear that sne has done a better job maintaining sensitivity during the shrinking process?
hope everyone enjoyed their new year and that you all have a safe and happy new year going forward.
EK
Why would ASUS want crappy 1.1um pixels when they could have nice big 1.4um pixels? In pixels, bigger is always better. 1/4" 8MP would be cheaper and smaller and give a poorer image quality with less sensitivity, less dynamic range and more noise.
DeleteWhy are two TSV's needed per bondpad?
ReplyDeleteI don't think these are TSVs. They look like ESD protection devices to me.
ReplyDeleteTSV openings are circular not rectangular.
Also why would they have both TSVs and wirebonds?
This is a BSI (BI?) device so the silicon is only a few microns thick. They are vias that are connecting the bondpad metal to the Copper interconnect. But not TSV's as they only go through the dielectric, the thin Silicon has been removed from the die edge.
ReplyDelete