The Internet of Things (IoT) has transformed the way we live and work by connecting countless devices and allowing them to communicate with each other. As IoT continues to expand, developers face an important decision when designing IoT products – whether to use a wireless module or a system-on-a-chip (SoC). This article examines the key differences between wireless modules and SoCs to help determine which is the better choice for your specific IoT application.

Introduction

A wireless module contains the components required for wireless communication, such as a microcontroller, radio transceiver, antenna, and protocols. Modules are designed to handle wireless connectivity so developers can focus on the end-node application. System-on-chips integrate the functionality of multiple components onto a single chip. SoCs contain a microcontroller, memory, peripherals, and wireless connectivity. While wireless modules simplify wireless communication, SoCs consolidate more components into a compact design.

When selecting between these two options, developers must consider factors like design complexity, customization, certification, cost, power consumption, and processing capabilities. The right choice depends on the specific needs and constraints of the IoT product. This article explores the pros and cons of each approach to help guide your decision making.

Design Complexity

One of the main advantages of wireless modules is easier and faster development. Modules handle the wireless connectivity, allowing developers to focus on the end-node application. The wireless stack and firmware are already integrated and optimized by the module vendor. This significantly reduces design complexity, risk, and time to market.

In contrast, SoCs require integrating the wireless stack and developing the supporting firmware. While SoCs offer more hardware control, they also involve more effort on low-level software and integration. This development effort translates to higher design risks and longer timelines.

Customization

Wireless modules provide limited customization since most of the module is fixed. Developers can tune only the external interfaces like UART, SPI, and GPIOs. With SoCs, developers have direct control over the hardware and can customize the chip configuration, peripherals, and wireless features for their specific application.

SoCs are better suited for products that need optimized or differentiated wireless capabilities. For example, custom wireless modes, security features, or peripheral interfaces. Modules offer less flexibility but simplify development for standard wireless connectivity.

Certification

Wireless technologies like Bluetooth and WiFi require extensive certification for regulatory compliance and interoperability. Modules undergo this certification process so developers don’t have to. SoCs may still need certification depending on the wireless implementation. Certifying an SoC requires advanced engineering resources and can get costly. Modules reduce the barriers of wireless certification.

Cost

Both wireless modules and SoCs aim to provide wireless connectivity at low costs suitable for IoT devices. In terms of manufacturing, SoCs have higher NRE costs for the chip design but lower per-unit costs at high volumes. Modules avoid the NRE costs but have higher per-unit costs. At low to medium volumes, modules can be more cost effective than SoCs.

Power Consumption

Minimizing power consumption is critical for battery-powered IoT endpoints. In general, SoCs are designed for ultra low power operation with advanced power saving modes. While modules also aim for low power, the power optimization may not be as extensive since it’s split over two chips – the module and the microcontroller. The integration of an SoC can enable lower overall power consumption.

Processing Capabilities

Wireless modules only provide wireless connectivity – the application processing occurs separately on an external microcontroller. SoCs include both wireless connectivity and an integrated application processor. This consolidation simplifies the design. It also enables easier integration between the wireless functionality and the application code.

SoCs can balance wireless tasks and application processing on a single chip. This on-chip integration unlocks capabilities like sensor fusion using data from multiple sources. For applications with more complex processing requirements, an SoC may be better suited than an off-chip wireless module.

Conclusion

Wireless modules simplify IoT development by handling wireless connectivity so developers can focus on the end-node application. SoCs provide more customization and integration but require greater design effort. When selecting between these two approaches, consider factors like design complexity, cost, power, certification, and processing needs. Wireless modules offer fast development while SoCs enable fully customized wireless and optimized designs. The right choice depends on the priorities, resources, and constraints of your specific IoT product.