A System on Chip (SoC) is a microchip that integrates all components found in a computer onto a single chip, making it function as a whole computer. It contains a microcontroller, microprocessor or digital signal processor core, memory blocks like RAM and ROM, timing sources, peripherals, external interfaces, analog interfaces, and power management circuits. While a microcontroller typically has under 100kB of RAM and is a single-chip system, an SoC is more powerful and requires external memory to run software like desktop operating systems. It allows smartphones and tablets to function as smaller computers by integrating all necessary components onto one chip.

1. Systems overview

2. System on chip
• What is a System on a Chip?
Since smartphones and tablets are basically smaller computers,
they require pretty much the same components we see in
desktops.
• System on Chip is a microchip that has all the components
required to power a computer.
• In brief , it is a computer on a chip.
• When it is not feasible to construct a SoC for a particular
application, an alternative is a system on package (SiP)
comprising a number of chips in a single package.

3. Difference between
microcontrollers and SOCS
• Microcontrollers typically have under 100 kB of
RAM (often just a few kilobytes) and often really
are single-chip-systems, whereas the term SoC is
typically used for more powerful processors,
capable of running software such as the desktop
versions of Windows and Linux, which need
external memory chips (flash, RAM) to be useful,
and which are used with various external
peripherals

4. Structure
• A microcontroller, microprocessor or DSP core(s). Some
SoCs—called multiprocessor system on chip (MPSoC)—include
more than one processor core.
• Memory blocks including a selection of ROM, RAM, EEPROM
and flash memory.
• Timing sources including oscillators and phase-locked loops.
• Peripherals including counter-timers, real-time timers and
power-on reset generators.
• External interfaces including industry standards such as USB,
FireWire, Ethernet, USART, SPI.
• Analog interfaces including ADCs and DACs.
• Voltage regulators and power management circuits.

5. ARM SoC Block Diagram