A System On A Chip (SoC) is an Integrated Circuit (also known as a “chip”) that integrates all or most components of a computer or other electronic system. These components almost always include a Central Processing Unit (CPU), memory, input/output ports and secondary storage, often alongside other components such as radio modems and a graphics processing unit (GPU) – all on a single substrate or Microchip. It may contain digital, analog, mixed-signal, and often radio frequency signal processing functions (otherwise it is considered only an application processor).
Higher-performance SoCs are often paired with dedicated and physically separate memory and secondary storage (almost always LPDDR and eUFS or eMMC, respectively) chips, that may be layered on top of the SoC in what’s known as a package on package (PoP) configuration, or be placed close to the SoC. Additionally, SoCs may use separate wireless modems.
SoCs are in contrast to the common traditional motherboard-based PC architecture, which separates components based on function and connects them through a central interfacing circuit board. Whereas a motherboard houses and connects detachable or replaceable components, SoCs integrate all of these components into a single integrated circuit. An SoC will typically integrate a CPU, graphics and memory interfaces, hard-disk and USB connectivity, random-access and read-only memories and secondary storage and/or their controllers on a single circuit die, whereas a motherboard would connect these modules as discrete components or expansion cards.
An SoC integrates a Microcontroller, microprocessor or perhaps several processor cores with peripherals like a GPU, Wi-Fi and cellular network radio modems, and/or one or more coprocessors. Similar to how a microcontroller integrates a microprocessor with peripheral circuits and memory, an SoC can be seen as integrating a microcontroller with even more advanced peripherals. For an overview of integrating system components, see system integration.
More tightly integrated computer system designs improve performance and reduce power consumption as well as semiconductor die area than multi-chip designs with equivalent functionality. This comes at the cost of reduced replaceability of components. By definition, SoC designs are fully or nearly fully integrated across different component modules. For these reasons, there has been a general trend towards tighter integration of components in the computer hardware industry, in part due to the influence of SoCs and lessons learned from the mobile and embedded computing markets. SoCs can be viewed as part of a larger trend towards embedded computing and hardware acceleration.
SoCs are very common in the mobile computing (such as in smartphones and tablet computers) and edge computing markets. They are also commonly used in embedded systems such as WiFi routers and the Internet of Things.