System Module Choices

What are SiP, SoC, COM, and SOM devices and what are the pros and cons of each?  What is the best fit for each module and how do they compare to the more traditional ‘chip down’ approach?  In this post, we will take a short walk through each type, give product example links and suggest how these approaches can be useful to your next product development or technology refresh.  We will also outline how a design firm such as Tauro Technologies can enable you to choose the best path and migrate from one form factor to the next as it makes sense for your projects.

New designs in past product generations tended to be chip down and were application and product specific.  As computing silicon has become more robust and complex, industry bodies such as PICMG pioneered standards that enabled companies to produce modules of standardized computing elements, giving product management teams a much simpler task of developing carrier specific to the required application features.

System on Module (SOM) & Computer on Modules (COM)

The terms SOM & COM are used interchangeably and are widely accepted as synonyms.   There are many companies manufacturing to the industry specifications  and global distributor Avnet provides a product selection guide offering a wide range of vendors and applications.  Further, there are building blocks widely available for specialized applications such as SDR or IIoT that will save significant time and money.

SOMs provide the building blocks of the application computing thus saving time and money to get the application to market, they also require broad-based engineering skills to build the application specific carrier.  Tauro Technologies works closely with many COM vendors and creates the carrier boards to integrate application I/O into these modules and develop firmware and software to enable the hardware to fit into the final product.

Pros	Cons
Many vendors with readily available products and low costs make it quick and easy to develop a new product.	Application specific I/O can be difficult to find.  User may be constrained by the vendor’s offering and implementation of the standards-based pinout.  COM-HPC is being released to help address this problem.
Open Standards such as PICMG COM Express ensure the products will be widely available for the coming decade.	Vendors may be slow to release a full set of products with the latest CPU, FPGA, GPU or I/O silicon.
End user can leverage available COM modules and customize a carrier board for I/O which is less risky and quicker to market.	SoM and COM solutions increase overall packaging size of the product making them unwieldy in certain applications.

FPGA based System on Chip (SoC)

Yesterday’s computing had separate blades connected over a backplane in a shelf or chassis.  The applications had complex hardware and software designs physically taking racks of computing space.  Today it is possible to have these massive systems of complex multi-board & multi-vendor products reduced to a single chip by vendors such as Intel and Xilinx.  The Xilinx SoC portfolio is an example of that integrates combinations of CPU, FPGA, GPU, Memory, RF and other peripherals on a single chip making it faster, easier and cheaper to create a new product.  The application is less prone to field failure and much simpler to upgrade with a software release vs a hardware swap.

Just as the development of systems in a multi-blade design required a large multi-discipline team, implementing SoC designs requires specialized knowledge and experience.  Tauro Technologies combines years of communications, RF, FPGA, and I/O experience and has deployed SoCs to communications, military, and industrial applications. 

Pros	Cons
Higher level of integration compared to distributed system.	Higher cost compared to ASIC based solutions.
Optimized thermal characteristics and power consumption.	Requires multidisciplinary team of highly skilled engineers to deliver the final product.
Reprogrammable FPGA fabric allows for future product improvements including new features.

System in Package (SiP)

SiP has been around since the 1980s and has recently been gaining traction – market researchers predict a high CAGR of this technology in the next 5 years.  Potential to integrate components such as DRAM, Flash and CPU into a single package makes it very attractive to application developers.  Where a SoC approach integrates these components into a single chip, the SiP approach combines separate chips into the same package which is then designed into the PCB.  The advantage again is that the design of the application specific portion of the printed circuit board is much simpler and lower cost.

Tauro Technologies designs systems based on SiPs for specialty applications where Size, Weight, and Power (SWaP) are critical for the application and can advise on the feasibility of this approach. 

Pros	Cons
Stack horizontally or vertically reducing package size, weight and cost.	High repair cost due to single component failure.
Complex systems are compacted into a simple package making integration and PCB layout much simpler.	Limited selection of available platforms and architectures.
Less effort during redesign due to the fact that all complex components are packed inside the SiP

Chip Down – Customized Design

The best design option for many large-scale projects or products that are deployed in harsh environments is a custom design that grants full control of the design and components.  Before SOM, SoC, and SiP were widely available, most products were designed by teams of engineers focused on hardware designs that were targeted to the efficiency, cost, and functionality requirements of the application.

SiP and SoC solutions essentially also are ‘chip-down’ solutions.  SoC combines many discrete components into a single chip whereas SiP is a variation of SoC packaging the discrete devices (Processor, DRAM, Power etc) onto a single IC package.

While fewer new designs will go a complete custom designed route, there are still many applications where this design approach is the best alternative.  Tauro Technologies’ provides experience in many such applications and can bring to fruition even your most complex concepts.

Pros	Cons
Not subject to vendor availability and lead-times.	Longer development cycle.
Easier to integrate into rugged systems for harsh environments.	Higher PCB design and manufacturing complexity.
Easier to port legacy systems to an upgraded hardware solution during a tech refresh.   Not subject to Vendor lockdown of components and firmware architectures.	Changing to different platform requires complete redesign of the system.
High volume production is lower cost.

Summary

SOM, SoC, and SiP give many advantages to help get application hardware to market.  As the product matures, it can be advantageous to take the standardized elements and create a hybrid or complete chip-down design to maximize efficiency and optimize cost.  Each product and project is unique, thus no one strategy fits all. 

Reach out to us to discuss the feasibility and benefits of these technologies for your next project.