IC vs Modules: Understanding the Technical Tradeoffs for IoT Applications

As the IoT continues to transform industries, design decisions around wireless connectivity components become increasingly complex. Engineers often face the dilemma of choosing between ICs and wireless modules for their IoT applications. Both options offer unique benefits and trade-offs, impacting factors such as design complexity, cost, scalability, and time to market. This blog explores the technical considerations and challenges associated with each, drawing insights from Silicon Labs' expertise in wireless solutions. We’ll provide a technical comparison between ICs and modules, highlighting the key differences, benefits, and hidden costs associated with each approach.

Understanding ICs and Modules

An IC (SoC) is a semiconductor device that contains a processor, memory, and other functional elements on a single chip. Engineers designing with ICs must develop a supporting PCB, including antenna design, RF matching, power management, and other components.

A module, on the other hand, is a pre-integrated system that includes an IC along with all necessary supporting components, such as RF-pin/built-in antenna, EMC shielding, power supply filtering, RF matching components, antenna components, and worldwide regulatory certifications. Modules are designed to minimize the hardware environment required to implement a complete solution, reducing design complexity and certification efforts.

Design and Development Considerations for ICs and Modules

RF Design Complexity

• IC: RF engineers must meticulously design and optimize antenna layouts, PCB trace lengths, and matching networks. Even slight variations in layout can degrade signal performance, requiring extensive debugging.
• Module: Pre-optimized RF design eliminates the need for complex antenna placement and matching, reducing development time and effort.

Certification and Compliance

• IC: Products using SoCs require separate regulatory approvals for each target market (FCC, CE, etc.), which can be costly and time-consuming.
• Module: Modules come with pre-certified regulatory approvals, significantly reducing certification costs and risks.

Time to Market

• IC: The complexity of RF design and certification can delay product launches by 3-6 months.
• Module: Faster development cycles enable quicker market entry, a crucial advantage for competitive industries.

Cost Analysis

• IC: Lower initial component costs, but higher design and certification expenses. Suitable for large-scale production where economies of scale justify the investment.
• Module: Higher per-unit costs, but reduced design and development expenses. Ideal for low to medium production volumes.

Hidden Costs of IC Design

As highlighted in the Silicon Labs whitepaper, “Six Hidden Costs in a Wireless SoC Design,” designing with SoCs introduces hidden costs that are often overlooked:

• RF Expertise: Hiring specialized RF engineers can cost $100,000 to $200,000 annually.
• Lab Equipment: Spectrum analyzers, anechoic chambers, and other RF test equipment can cost up to $50,000.
• PCB Layout: Achieving optimal antenna performance requires iterative PCB design and manufacturing cycles.
• Certification Costs: Regulatory testing for SoCs can exceed $50,000 over a five-year period.

SiP (System-in-Package) vs PCB Modules

When considering ICs and modules, another factor is the form factor used.

SiP Modules

System-in-Package (SiP) modules integrate multiple components into a single package, offering a compact solution with optimized RF performance with smaller size (<12mm x 12mm), pre-integrated components, advanced packaging techniques (e.g., stacked memory), optimized for high-performance applications and requires careful thermal and mechanical design.

PCB Modules

PCB modules consist of a carrier board with components mounted separately. They offer easier development and in-house prototyping, more flexible design changes, easier second sourcing, and generally larger size (>10mm x 10mm).

SiP Modules for Miniaturized IoT Designs

Silicon Labs’ System-in-Package (SiP) modules, such as the BGM220S, exemplify the benefits of module-based design. These modules feature integrated RF components and shielding, offering superior size and performance optimization for space-constrained applications like wearables and smart sensors. With a compact 6.5 mm x 6.5 mm footprint, SiP modules reduce PCB real estate while ensuring robust RF performance.

When to Choose IC vs Module

ICs are ideal when:

• High production volumes justify the upfront design and certification costs.
• The design team has access to RF expertise and advanced lab facilities.
• Custom RF optimization is critical for the application.

Modules are preferable when:

• Rapid time to market is essential.
• Regulatory certification costs need to be minimized.
• The application requires a compact and standardized design.

A Balanced Approach

The decision between IC and module depends on specific project requirements, resources, and business goals. Silicon Labs' ability to provide both solutions ensures that customers can seamlessly transition from modules to SoCs as their production volumes and design capabilities evolve. By partnering with a single supplier, companies can protect their software investment and optimize their IoT designs for long-term success.