Inside Of Samsung's 845DC EVO
Opening up the 845DC EVO gives us flashbacks to our coverage of the 840 EVO. Its PCB and general layout, along with most of the components, are identical. Samsung's consumer-oriented 840 EVO employs a smaller PCB, which creates more empty space inside the 2.5" chassis. But the 845DC EVO's circuit board is larger to accommodate the power-loss protection capacitors, filling the enclosure.
Samsung's 845DC EVO uses the same MEX 400 MHz triple-core Cortex-R4-based controller (labeled S4LN045X01-8030) as the 840 EVO.
Also, the same 1 GB of LPDDR2 DRAM cache is present on the largest 845DC EVO model.
As mentioned in the introduction, Samsung's 845DC EVO employs 3-bit-per-cell NAND. Our 960 GB review unit includes 1024 GiB of raw flash capacity. Each of the on-board packages contains eight dies, with 16 GiB per die. The spare area (12.7%) is greater than what the 840 EVO (9.05%) offers, helping improve consistency and extend the NAND's life.
In the above shot, you can see some of the 23 power-loss capacitors used to keep the SSD's controller running just long enough, in the event of an outage, to flush all pending writes.
Overall, Samsung appears to take a direct approach to the 845DC EVO's design, only making changes deemed absolutely necessary. After all, the 840 EVO is already a fairly mature platform.
