System-on-a-chip

System-on-a-chip or system on chip (SoC or SOC) is an idea of integrating all components of a computer or other electronic system into a single integrated circuit (chip). It may contain digital , analog ,mixed-signal , and often radio frequency functions – all on one chip. A typical application is in the area of embedded systems.

If it is not feasible to construct an SoC for a particular application, an alternative is a system in package (SiP) comprising a number of chips in a single package. However, SoC is believed to be more cost effective since it increases the yield of the fabrication and because its packaging is simpler.

A typical SoC consists of:

• One or more microcontroller , microprocessor or DSP core(s).
• Memory blocks including a selection of ROM ,RAM , EEPROM and Flash.
• 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 ADC and DACs.
• Voltage regulators and power management circuits.

These blocks are connected by either a proprietary or industry-standard bus such as the AMBA bus from ARM.DMA controllers route data directly between external interfaces and memory, by-passing the processor core and thereby increasing the data throughput of the SoC.

Proliferation of communications devices and the drive to reduce costs have necessitated the
current trend towards system-on-a-chip (SOC) designs.

No longer are solutions split among multiple chips with analog components separated from their digital counterparts. SOC chips require both elements to be on one silicon substrate.