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🚗 | ZF's next-generation in-vehicle supercomputer can calculate 1 trillion times per second ... Shanghai Motor Show 1000

Photo ZF Press Conference (Shanghai Motor Show 2021)

ZF's next-generation in-vehicle supercomputer can calculate 1 trillion times per second ... Shanghai Motor Show 1000

If you write the contents roughly
ZF ProAI is modular and can be mounted on system-on-chip (SoC) from various manufacturers.

ZF will hold a next-generation in-vehicle supercomputer at the Shanghai Motor Show 4 that opened in China on April 19th. → Continue reading


Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.


System-on-a-chip(SOC,SoC) IsIntegrated circuitOn one chip ofProcessorGeneral including coreMicro controllerIn addition to the functions that the system has, the functions for application purposes are also integrated and linked.システムIt is an integrated circuit product designed to function as an integrated circuit product.

Since there are various difficulties and risks associated with mixed loading of large-capacity DRAM and analog circuits, and there are also disadvantages (described later), the DRAM was integrated on a separate chip and housed in the same package.SiPSome products take the form of.

LSI specialized for improved integration and application

Mid-1970sMicroprocessorIs not yet highly integrated, so-calledCPUIt has only the function as (in recent years, it is also called the core etc.)memory,Parallel I / O,UARTPeripherals such as, used different chips, different packages, and mounted them on a printed circuit board (or by individual boards connected by a backplane) to form a system.

Since the 1980s, the so-called "one-chip microcomputer" has been integrated with the functions around the microprocessor on a single chip, partly due to the increased degree of integration.Micro controller) Has appeared.

In addition, by adding a specific dedicated circuit to the microcontroller according to the individual requirements of the customer, it has become possible to produce products that are optimized for the application, although the versatility is reduced.As a semiconductor maker, as a high value-added product that can increase the unit price of a chip, a set maker (a maker of a device that uses the chip) has been adopted in a device with a large number of shipments because it leads to cost reduction of the entire device.Such productsASICIt was called a custom chip (the CPU function is external, including peripherals and dedicated circuits integrated into a single chip).

The flow of integration continued and accelerated further for the following reasons.

  • Increased circuit scale of integrated circuits --- Improvements in semiconductor manufacturing technology have made it possible to realize multiple circuits of a scale that could not be integrated in the past on a single chip.
  • Sophistication of circuit design method Hardware description languageUsingEDADesign efficiency is improved by the design method using tools.The semiconductor process and functional level design have been separated, making it easier to reuse in functional block units (see details).IP coreSee).Circuits that had not been released outside the company until then are now distributed as IP cores.

A design method that meets these requirements and a semiconductor product manufactured by this design method are called SoCs.

The following is a comparison between the SoC (ASIC in general) integrated on one chip and the case where multiple single-function LSIs are mounted on the board.

  • Reduction of occupied area --It can be made smaller than mounting multiple IC packages individually on a printed circuit board.
  • Speeding up --Wiring on printed circuit boards between IC packages, package leads, etc.Impedance,Cross talkThe signal delay due to is reduced.PAD inside the chip[Annotation 1]Since the bus can be connected without passing through, the delay is reduced.
  • Low power consumption ――By connecting internally, you can reduce the number of terminals that do not need to be output to the outside and reduce PAD, and it is easier to incorporate the power saving function of the entire chip by the power saving technology "Gated Clock".
  • Cost reduction ――It is expected that the board will be reduced, the mounting and inspection will be simplified, the number of failures will be reduced, and if mass production is possible, the cost of the final product incorporated will be reduced.

It's unclear when the word SoC started to be used, but in 1994[1]There is information that.At that time, the names such as ASIC and microcomputer (abbreviation for microcontroller) became obsolete, and attracted attention as a new name that gives an impression of high added value. Since the time when design methods based on the premise of using IP cores became mainstream, the term SoC has been used more and more.Initially System on a Chip (SoC)[Annotation 2]Besides, it was also called System on Silicon (SoS), but gradually settled down to SoC.

Also, as a word with a meaning close to SoC,System LSIThere is the word.

Mixed loading of DRAM and analog circuit

It is an SoC that means that the entire circuit of the entire system can be mounted on one chip, but it may also refer to one that also has a large-capacity memory and analog circuit in addition to the above digital circuits.

Even a conventional microcontroller is relatively small (several kilometers)Part-Time JobFrom several hundred kilobytes)SRAM,ROMAlthough it was equipped with (including mask ROM and flash memory), it was difficult to realize it with a capacity exceeding several megabytes, and it was necessary to use an external memory.Larger memory capacity than SRAMDRAMSince the above is suitable, mixed loading of logic circuits and DRAM has been attempted from the past, but it was difficult to realize because the semiconductor manufacturing process is different. DRAM mixed loading process was realized around 1998[2] However, due to the problems described below, it is not optimal for all applications.

In addition, analog circuits often require a semiconductor manufacturing process different from that of logic circuits, and it has been difficult to mount general-purpose analog circuits in large-scale logic LSIs. In the previous microcontroller products called SoC, some circuits such as A / D converters, D / A converters, and PLLs could be realized, but high-power transistors for power supplies, high-precision operational amplifiers, and RFs that handle high frequencies Circuits are difficult to mix.There is also the term Mixed Signal, which refers to mixed digital / analog circuits.

As of 2007, SoC does not necessarily include DRAM and analog circuits.

Technical challenges and risks

SoC has advantages / disadvantages, and the following points are mentioned as disadvantages.

  • Complex development process
    • Prolonged development period
    • Cannot respond immediately to specification changes
    • Excessive risk in terms of time and cost when remanufacturing due to design failure
  • Increased die area
    • Yield decrease Increase in chip manufacturing cost
  • Difficult to handle small quantities and many types Information appliancesIn the field, it is also related to shortening the product life
  • With the miniaturization of semiconductor processesPhoto maskSoaring charges (this problem is not limited to SoCs, but integrated circuits in general)

When DRAM and analog circuits are mounted together, the following points are also problematic.

  • Increased number of processes and photomasks due to mixed loading of different processes
    • Increased manufacturing costs
    • Negatively impacts yield

Although there are these technical issues and risks, they can be overcome by improving the semiconductor manufacturing process technology, improving the methodology (design and development method), flexible specifications considering these, and developing DFT / DFM technology. Is being done.If you don't have any know-how about these, the risks are still high.

In addition, from these circumstances, another method for manufacturing a large-scale integrated circuit is also required, and as a means for solving the above problem.SiPHas begun to attract attention. SiP was put into practical use in the early 200x's[3], It is designed to make up for the weaknesses of SoC. (As of 2007) SoC is not completely denied by SiP, and if development and manufacturing proceed smoothly, the cost reduction effect due to the mass production effect will be large, and it will be used properly depending on the situation, or SoC and SiP will be used in combination.


[How to use footnotes]

注 釈

  1. ^ Area for connecting external terminals of integrated circuits.Since bonding wires and bumps are connected, it occupies a large area compared to the internal logic cell.It needs to output more current than the internal logic cell and contains a large transistor.
  2. ^ The article a is required because chip is a countable noun.


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