System-on-a-chip or system on chip (SoC or SOC) refers to integrating all components of a
computeror other electronic systeminto a single integrated circuit(chip). It may contain digital, analog, mixed-signal, and often radio-frequencyfunctions – 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. In large volumes, SoC is believed to be more cost effective than SiP since it increases the yield of the fabrication and because its packaging is simpler. [ [http://www.eetimes.com/showArticle.jhtml;?articleID=159901628 The Great Debate: SOC vs. SIP] ]
A typical SoC consists of:
microcontroller, microprocessoror DSP core(s). Some SOCs -- called multiprocessor System-on-Chip ( MPSoC) -- include more than one processor core.
Memoryblocks including a selection of ROM, RAM, EEPROMand Flash.
* Timing sources including
oscillators and phase-locked loops.
* Peripherals including
counter- timers, real-time timers and power-on resetgenerators.
* External interfaces including industry standards such as USB,
FireWire, Ethernet, USART, SPI.
* Analog interfaces including ADCs and DACs.
Voltage regulators and power managementcircuits.
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.
A SoC consists of both the hardware described above, and the software that controls the
microcontroller, microprocessoror DSP cores, peripheralsand interfaces. The design flow for an SoC aims to develop this hardware and software in parallel.
Most SoCs are developed from pre-qualified hardware blocks for the hardware elements described above, together with the software drivers that control their operation. Of particular importance are the
protocol stacks that drive industry-standard interfaces like USB. The hardware blocks are put together using CAD tools; the software modules are integrated using a software development environment.
A key step in the design flow is
emulation: the hardware is mapped onto an emulation platform based on a field programmable gate array(FPGA) that mimics the behavior of the SoC, and the software modules are loaded into the memory of the emulation platform. Once programmed, the emulation platform enables the hardware and software of the SoC to be tested and debugged at close to its full operational speed.
After emulation the hardware of the SoC follows the
place and routephase of the design of an integrated circuitbefore it is fabricated.
Chips are verified for logical correctness before being sent to foundry. This process is called functional verification, and it accounts for a significant portion of the time and energy expended in the chip design life cycle (although the often quoted figure of 70% is probably an exaggeration [ [http://www.eetimes.com/showArticle.jhtml?articleID=21700028 Is verification really 70 percent?] ] ).
Verilogand VHDLare typical hardware description languages used for verification. With the growing complexity of chips, hardware verification languages like SystemVerilog, SystemC, e, and OpenVeraare also being used. Bugs found in the verification stage are reported to the designer.
SoC designs usually consume less power and have a lower cost and higher reliability than the multi-chip systems that they replace. And with fewer packages in the system, assembly costs are reduced as well.
However, like most VLSI designs, the total cost is higher for one large chip than for the same functionality distributed over several smaller chips, because of lower yields and higher NRE costs.
List of system-on-a-chip suppliers
Electronic design automation
Post silicon validation
* [http://www.ibm.com/developerworks/views/power/libraryview.jsp?search_by=SoC+drawer:&ca=dgr-wikiaSoCSeries SoC Article Series]
* [http://www.teridian.com/products/product_detail.cfm?product_key=60 TSC electric power meter IC] - a typical mixed-signal system on chip
* MIPS-based [http://www.linux-mips.org/wiki/SoC SoCs] at [http://www.linux-mips.org/ linux-mips.org]
* [http://www.hwswworld.com/journal.php Frontier Journal]
* [http://www.linuxdevices.com/articles/AT4313418436.html Embedded Processor and System-on-Chip Quick Reference Guide]
* [http://www.siliconfareast.com/soc.htm System-on-a-Chip] by www.SiliconFarEast.com
* [http://www.na2.es/home.htm Navarre AsyncArt. Asynchronous System-on-Programmable-Chip Research & Services. Public University of Navarre]
* [http://www.ittc.ku.edu/hybridthreads HybridThreads(Hthreads)] Programmatically building semi-custom multiprocessor systems-on-chip using hybrid CPU/FPGA components.
* [http://wiki.ittc.ku.edu/ittc/Eecs388 MicroBlaze-Based Introduction To Computer Architecture and Assembly Language for Systems-On-Chip]
* [http://www.nakshatechnologies.com Systems-on-chip using hybrid CPU/FPGA components.]
* [http://www.tertiumtechnology.com/soc_arm_inside_en.php Soc ARM Inside] by www.tertiumtechnology.com
* [http://www.ieee-socc.org/index.html SOCC] Annual IEEE International SOC Conference
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