Everything You Need to Know About Full Custom ASICs: The Complete Guide
Are you interested in custom silicon? Full Custom ASICs are top-of-the-line custom designs in modern technology, offering optimised solutions for performance, power, and area that generic alternatives simply can’t match. You might be designing a consumer electronic product, automotive systems, high-performance computing or something else. Full Custom ASICs may be the difference-maker in your product.
In this definitive guide, we explore the ASIC design flow, explain why a custom ASIC design is so significant, and discuss the benefits of working with an experienced ASIC design consultation team.
What Is a Full Custom ASIC?
A Full Custom ASIC is a special-purpose chip: every transistor, gate, and logic component is designed from the ground up to fill a very specific set of functional requirements. This allows for maximum optimisation in performance, power consumption, and size, and it can be applied in very high-end applications for which solutions off-the-shelf like FPGAs, or even semi-custom ASICs can no longer meet the very stringent requirements.
Unlike semi-custom ASICs, which use pre-designed blocks called standard cells, full custom ASICs are designed at the transistor level. This makes it open to additional control by designers but also increases the design complexity.
ASIC Design Flow
The process of developing a Full Custom ASIC is very detailed and has various steps, each important to the complete functionality of the chip based on its specifications. Here is an overview of the ASIC design flow:
- Specification: The first aspect of ASIC design is gathering the functional requirements for the chip. This would mean knowing the expected application, desired performance, power constraints, and area constraints.
Interactive Insight: Now imagine you are designing a chip for a smart-wear device. What kind of KPIs would you focus on? More of a battery-life issue, fast computation speed, or sensor accuracy?
- Architecture Design: Having determined the specifications, actual architecture design begins. Here is where the overall structure and organization of the chip are decided. How will it flow? Memory management techniques will be used. Will it be a demand-paged virtual memory system?
- Logic Design: After architecture, the design activity is logic design. The functional blocks of the ASIC are expressed in HDL hardware description language like VHDL or Verilog. Read about HDL design and how it is done.
- Circuit Design: While in Full Custom ASICs, the circuit design is the most important step where logic is translated into circuits by designing individual transistors and gates, semi-custom designs are different where standard cells are pre-designed.
Pro Tip: For a low-power-sensitive design, this is a proper place to focus on low-power techniques, for example, multi-threshold CMOS or leakage optimisation.
- Physical Design: In physical design, the circuit design is mapped to a layout that the manufacturer can use. Some of the tasks involved in the steps of this stage include the placement of transistors, routing of wires, and checks to ensure that there are no violations of the rules of design. More on physical design – learn how it is important towards achieving your performance goals.
- Verification & Testing: No ASIC design is considered complete without thorough verification. Formal verification and simulation tools are applied to check whether the design works as expected. After validation, such a design is tested after its fabrication to catch any manufacturing defects.
- Fabrication: This final step is sending the verified design off to a fabrication facility, commonly referred to as a foundry, which will make the chip. For further information on ASIC fabrication details, click here for the detailed process of fabrication and why it is important.
A flow of design for each step contains speciality work, whose achievement often requires the help of engineers with years of experience in the domain. That is why a collaboration with an ASIC design consultation service is quite recommended if the company does not have internal experts.
Why a Full Custom ASIC?
While off-the-shelf components like FPGAs and microcontrollers offer flexibility, they usually cannot match the efficiency of Full Custom ASICs in terms of power consumption, performance, and area optimisation. Here are some compelling reasons to choose a Custom ASIC:
- Performance Optimisation: A Full Custom ASIC provides the ultimate level of performance tuning because every transistor can be optimized for an application’s specific needs.
- Less Power Consumption: Designers can fully optimize the design at the transistor level when reducing power consumption by many folds. This is a most important consideration in mobile, wearable, or IoT devices because battery life happens to be very critical.
Do you know? Apple uses Full Custom ASICs in their devices, like the M1, to provide extreme performance with minimal power consumption.
- Area Efficiency: Full Custom ASICs are designed much smaller compared to a semi-custom solution, and hence free up some precious real estate on your PCB.
- Security: A custom design can also include security features like encryption engines or PUFs that are not available with off-the-shelf components.
Learn more about PUFs and how they improve security in full-custom ASICs.
The Role of ASIC Design Consultation
Custom ASIC is one of the most difficult pieces of design for engineers. For most companies, it would be worthwhile to engage with an ASIC design consultancy company that would help in overcoming and searching through challenges such as:
- Meeting power and performance targets.
- Managing the fabrication cost and risks.
- Ensuring manufacturability and testability.
A good consulting service will also maintain close relations with foundries and packaging vendors to further help ease the way from concept to production.
Cost Factors
The non-recurring engineering costs of Full Custom ASIC design are quite high mainly for its long development cycle and due to the fact that it utilizes highly specialized tools and personnel. However, once the design is done, unit costs plummet with volume, making it a premier option for high-volume production environments.
In addition, Full Custom ASICs are now more accessible to startup and mid-sized companies due to modern design tools along with IP cores that go with consultancy services. Explore IP cores in the development of Full Custom ASICs.
Applications of Full Custom ASICs in Real Life
Full Custom ASICs find their applications in many products. Popular applications include:
- Consumer Electronics: Chips in smartphones, tablets, and wearables can be customized to achieve robust performance while also allowing for effective power management.
- Automotive: Custom ASICs are commonly used by autonomous driving systems and powertrain hardware to perform real-time processing and make decisions. Click here to learn about automotive ASICs and their importance in the automotive sector.
- Telecom: ASICs in a 5G base station optimize bandwidth and power, which means speeding up data transfer with reduced latency.
Conclusion
In a world that constantly asks for more – higher performance, lower power consumption, and smaller form factors, ASIC design is a very powerful solution. The whole flow of ASIC design, with expert consultation through experienced ASIC design consultants, is utilized and fully manifests its potential to unlock custom silicon designed precisely to their needs in companies.
When you decide to move forward with creating a Full Custom ASIC, it is extremely important to have a capable partner who can guide you through the complexities of the design and fabrication process. Learn more about ASIC design consultancy and Full Custom ASICs from Nano Genius Technologies and take your first step toward custom silicon today!
Frequently Asked Questions
- What do I know about the difference between a Full Custom ASIC and an FPGA?
The full custom ASICs are designed at the transistor level, which provides maximum optimization for performance, power, and area. FPGAs, however, are applied as reconfigurable devices that use pre-designed logic blocks. They are more flexible but less efficient.
- How long does it take to design a Full Custom ASIC?
ASIC design typically ranges from 6 months to 2 years, depending on the ASIC design complexity and the experience of the design team. Discuss several factors influencing ASIC design timelines.
- Is it expensive to develop a Full Custom ASIC?
While the upfront costs are high due to design and fabrication, the unit cost drops significantly for high-volume production. Full Custom ASICs are usually cost-effective for products with large production runs.