Samsung's Exynos Line of SoCs
Unlike Qualcomm, Apple, and now Nvidia, Samsung doesn’t design its own CPUs. Instead, it licenses both the CPU and GPU logic from ARM. However, one advantage Samsung has is that it manufactures the chips itself, and doesn’t have to pay other foundries to do it.
Exynos Series
Samsung shipped its first Exynos (3) SoC in 2010 alongside its highly successful (at the time) Galaxy S smartphone. Exynos 3 came with a single-core 1 GHz Cortex-A8 CPU, which, at the time, was the only popular mobile processor in an Android device that wasn't a Snapdragon. Apple launched its iPhone 4 around the same time that also featured a Cortex-A8, though that one operated at 800 MHz.
A year later came the Exynos 4210, Samsung’s first dual-core chip, which appeared in the company's Galaxy S2. It included Mali-400 graphics, a part that went on to become quite popular in other devices.
Not long after, Samsung introduced the Exynos 4212 in its Galaxy Note with a host processing complex running 200 MHz faster and a GPU purportedly 50% quicker. The Note had a 1280x800 resolution, and of course that was quite a bit higher than the Galaxy S2's 800x480 screen, necessitating increased graphics processing.
In 2012, Samsung shipped its first quad-core chip, Exynos 4 Quad, inside the Galaxy S3 and Galaxy Note 2 smartphones. It also used 20% less power than the previous-generation SoC, while retaining a quad-core Mali-400 GPU.
Towards the end of the year, Samsung began using the Exynos 5 Dual, based on Cortex-A15, in its Nexus 10 tablet. The processor was significantly more powerful even than the Exynos 4 Quad and had Mali-T604 graphics employing the new unified shader Midgard architecture. This chip was also used in the most popular Chromebook device at the time, helping the machine hit a low $250 price point, while offering respectable performance.
Exynos 5 Octa
In 2013, Samsung shipped its first eight-core chip for the Galaxy S4 and Galaxy Note 3. It was named Exynos 5 Octa, or Exynos 5410.
Exynos 5 Octa was the first SoC based on ARM's big.Little configuration, made of four-core Cortex-A7 and Cortex-A15 CPU clusters able to work separately to save battery life or together for maximum performance.
The part ended up with several issues, many related to firmware. This wasn't surprising, given the technology's newness. Samsung’s engineers were still learning how to make the Cortex-A7s and -A15s work well together, in the most energy efficient way. Because of those problems, and because Qualcomm had better LTE modem integration in its SoC, Samsung continues using Snapdragon processors in most of its markets.
To make matters even more complicated, Samsung also stepped back to using PowerVR graphics for this SoC, instead of the Mali architecture. Presumably, it did that because ARM’s Mali-T628 wasn’t ready, giving the company no other choice.
This year, Samsung changed direction again and went back to Mali-T628MP6 graphics. It also seems to have fixed the issues with Exynos 5 Octa in a new Exynos 5422 version. The latest revision also sports a 300 MHz boost to its Cortex-A15 cores and an extra 100 MHz for the Cortex-A7 cores. Moreover, Samsung added a mode that makes all eight cores operate at the same time, when needed, rather than completely separate the two clusters.