Design of wireless devices: chip-on-board or module?

If your company decided to design a new product with the support of WiFi, BLE, Zigbee, or LoRa, you are faced with a choice between a wireless system-on-chip (SoC) and a ready-made wireless module. It’s necessary to address them separately.

Wireless system-on-a-chip: you get a cheaper and smaller solution

Wireless SoC, a microcontroller that integrates RF front-end, digital I/O and low power processor core. It may cost three times less than a module. But does that mean that the total cost of the development will be less? Not always because the SoC requires additional spendings.

First of all, you will need well-paid radio-frequency engineers and expensive lab equipment. Be prepared to spend the time on RF design, as it typically requires several iterations of prototype manufacturing. Your team should be able to do antenna design correctly and debug all the issues.

So if you are planning to choose wireless SoC, keep in mind that possible time-to-market delays can reduce your ROI (return on investment). We know that engineers get really excited when they have a chance to design everything on their own but the market does not care about this enthusiasm. Time-to-market is still the strongest argument for business people. Keep a cool head and try to foresee possible issues with your SoC-based design process.

Wireless module: you don’t need deep expertise in RF design

Despite the bigger size and higher price, the wireless module has a number of advantages. You can forget about the design of a printed circuit board with a wireless SoC onboard. It means that the module assumes RF layout, optimized antenna, etc., thus your engineer can focus on developing low complexity tasks such as carrier board and microcontroller firmware. Also, most of RF modules do not need further standard certification and regulatory approvals as RF module vendor typically take care about getting certifications. Contrary, with wireless SoC approach, you have to pass full-range RF certification tests in an accredited lab, which is far more expensive than traditional FCC and CE tests.

Promwad tech expert Ivan Kuten explains:

"It's impossible to make a choice between SoС and SoM once and for all. Every time you should consider the details of your project. And it's always a trade-off. Do you have in-house design expertise? What is your project budget and expected time-to-market? Where are you going to test and certify your product? What are your planned production volumes and the size of your product? And this is only a part of all the questions on this issue, not to mention the technical requirements”.

There is a large market of ready-made solutions for wireless devices. For example, Promwad works with SoC and modules of companies as Nordic Semiconductor, Qualcomm, Texas Instruments and Silabs for its electronics design projects.

We know that it the right choice between wireless SoС and module is a difficult question for engineering teams without relevant experience, so feel free to contact us to discuss the development of their device.


Photo: SoC CC3200R1M2RGCR by Texas Instruments and CPU module based on the TI DM3730 by Promwad.