It does so because it contains the same sort of hardware.
To get around the significant space constraints, an entirely new design paradigm is used.
The SoC contains a CPU, but it also contains far more than that.
If it helps you’re able to assume the a is in parentheses and goes assumed but unsaid.
What does an SoC contain?
It really depends on the SoC and what its intended for.
It does need to contain at least one processing core.
Typically, an SoC will contain multiple processing cores, though some simple products may only use one.
An SoC must also contain some sort of interconnect to connect different components on the chip.
Tip: A NoC is not to be confused with a NOC or data pipe Operations Centre.
Pretty much everything else is optional, though more must be contained for it to be an SoC.
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Why choose an SoC?
Typically, an SoC will be a single monolithic silicon chip.
These 3D designs tend to still be referred to as single chips and so are SoCs.
An SoC that makes use of distinct chiplets is differentiated as a System In Package or SIP.
Nevertheless, space challenges do occur.
Packing a lot of processing power together also means there can be a lot of heat production.
Combined this means that compromises must be made to ensure a stable system.
For direct end-user devices, a balance between high power efficiency and high performance must be found.
By placing everything on a single chip, latency is minimised and higher bandwidths can be achieved.
Additionally, the power needed to communicate signals is reduced as cables are shorter.
With a tightly integrated chip, there is less to go wrong.
Additionally, manufacturing costs dont include costs for extra combination steps such as in a chiplet design.
Limitations of an SoC
The single biggest limitation of an SoC is the heat/power density.
It is difficult to cool devices, especially something like a smartphone that has to rely on passive cooling.
An SoC has to be tuned to its expected thermal envelope.
This is ultimately the performance limiting factor on smartphones.
As such the M1 and M2 chips offer significantly more processing power than a smartphone SoC.
There is a limit to this though.
Modern high-end CPUs and GPUs are already incredibly hot.
You simply cannot just integrate both into one great big SoC.
The thermal density would just be too high, and it would be essentially impossible to cool.
This can be seen with the shift already having started towards chiplet designs.
That said, computers are slowly integrating more and more features onto the CPU.
There are performance benefits to doing so.
This process is unlikely to extend too far though.
Mass storage, DRAM, and high-end graphics especially are unlikely to be integrated.
Conclusion
SoC stands for System on Chip.
It is not to be confused with SOC which stands for Security Operations Centre or Systems and Organisation Controls.
The core of the chip is the CPU but most other components and processing power are also directly included.
The SoC design paradigm has been extremely successful in the smartphone market.
SoCs can also be found in tablets and some thin-and-light laptops.
Given their market, SoCs are typically tuned for power efficiency with optional peak performance on demand.
This isnt necessarily integral to the design though.
