State-of-the-art wireless modules save time, space and money
Thanks to the emergence of the internet of things (IoT), no modern electronic device is complete without wireless connectivity, be it WiFi, Bluetooth, ZigBee or cellular/GSM. There are ultra low power protocols for even the smallest coin-cell battery powered sensors that report collected data to the cloud, right through to larger home appliances which are able to automatically update their own software via WiFi. LoRaWAN, an emerging low power, low bit rate technology is gaining ground, and a new cellular standard, NB-IoT, is set to bring unlimited reach to small IoT devices with global coverage using extensive, brand new infrastructure. What this means is that almost all of today’s electronic device designs will have to integrate some form of wireless connectivity or other. The easiest, quickest and cheapest way to do this is with wireless modules.
The alternative to a wireless module is designing, building and testing a discrete version of the same circuit. It’s fairly obvious that selecting a wireless module is a much quicker process; everything, even antenna and receiver placement, is already taken care of by the module manufacturer. Today’s modules are straightforward to integrate, shortening the development cycle considerably. For applications like consumer electronics where delays in time to market can mean the difference between a successful product and a disaster, every little bit of time that can be saved can make a big difference. There is also the matter of certification; sending products to the test house for certification can take weeks, but using a complete wireless module that comes pre-certified can minimise the testing burden and reduce the risk of having to wait for the design to go through certification more than once in the case of failures.
While wireless connectivity is a must-have for today’s electronic devices, many would argue that it isn’t worth putting extensive design resources towards a discrete implementation of the wireless sub-system, whose quality wouldn’t differentiate the product from its competitors anyway. These resources would be better directed towards adding features that really do differentiate the product, and using a wireless module enables that. Also, since the design of discrete RF circuits includes such design issues as layout, signal routing, layer stack-up, interference and shielding – all of which require specialist RF skills – selecting a module can mean this expensive specialist expertise is not needed.
ALPS’ UGMZ2AA Bluetooth low energy module has a built-in antenna and is amongst the smallest Bluetooth modules on the market
Performance is another area where RF modules compare favourably. Module manufacturers are experts at optimising designs for performance, footprint and other attributes, ensuring their products exhibit the best possible characteristics. These designs are proven over many iterations and generations. Manufacturers use the latest wireless ICs, maintaining close relationships with semiconductor companies, and combine them with the very best antennas available, which they get for the best possible prices. Again, while it’s perfectly possible to design and build a discrete RF connectivity sub-system that equals this performance, the amount of time and money you’d have to spend on it would make it unfeasible for all but the biggest operations (even Apple uses wireless modules – they have a Murata WiFi/Bluetooth module in the iPhone 7). For example, ALPS’ UGMZ2AA Bluetooth low energy module, the culmination of years of development of RF circuit expertise and precision processing technologies, has a built-in antenna and is amongst the smallest Bluetooth modules on the market at just 4.7 x 4.7 x 2.0mm. Its power consumption is just 5.1mA (0.6μA in sleep mode).
A more subtle advantage is the life cycle of modules versus wireless ICs. If a particular wireless IC goes obsolete, the module manufacturer can often change the IC inside their module to an alternative solution and rework the design so that the module retains the exact same functionality with the exact same dimensions and pin out, etc. This can lengthen a module’s lifespan considerably, with little implication for the customer in terms of redesign. Life cycle is crucial to some long-lived end products/applications, but even short-lived products can benefit from the security of supply offered by wireless module technology.
Fujitsu offers a complete, fully FCC/IC/CE/Japan radio
ACT certified Bluetooth 4.2 and NFC module built on the
Nordic nRF52 platform
For most applications, the combination of the design time and resources saved, avoiding the need for specialist RF engineers, the time saved by avoiding in-depth testing on a discrete circuit, and avoiding the need for specialist RF antenna matching and tuning equipment adds up to a significant financial savings versus other routes. Add into the equation the fact that modules are effectively pre-yielded – they are tested by the manufacturer – so there is less cost associated with failure analysis and rework, and the argument is compelling. The cost savings to be made from choosing a wireless module are so considerable that the market is adopting them almost without exception.
Wireless modules are available based on a wide variety of different platforms, so there is still plenty of choice. If your design team has experience with, or just an affinity for, any manufacturer’s wireless IC, there will be a suitable module available. Whether they prefer a Dialog chipset for its extremely low power consumption, or the Nordic Semiconductor nRF52 with its strong ancillary microcontroller and NFC support, module manufacturers offer plenty of options. For example, Fujitsu offers a complete, fully FCC/IC/CE/Japan radio ACT certified module featuring Nordic’s nRF52 SoC which enables the quickest possible time to market, while supporting both Bluetooth 4.2 and NFC technologies.
Murata's LoRa module measures only 12.5 x 11.6 x 1.7mm
in its metal-shielded package
Bluetooth modules are available either completely blank, for total flexibility, or with a software stack supplied by the module manufacturer, which simplifies development with a fixed set of commands to the transceiver from your MCU via UART. For example, Taiyo Yuden’s range includes the EYSGJNZWY Bluetooth low energy module which comes with a built-in antenna for the smallest and thinnest possible solution, but it’s available in versions with or without Taiyo Yuden’s specially designed software application, giving the customer the option to develop their own communications software.
If a product requires support for the latest cutting edge technologies, module manufacturers can still provide options. For example, Murata has released a wireless module for the emerging LoRaWAN sector, the CMWX1ZZABZ-078. This industry-leading module features a Semtech SX1276 ultra long range spread spectrum transceiver and an STMicroelectronics STM32L0 Cortex M0+ microcontroller with 192kbytes of Flash. This module measures only 12.5 x 11.6 x 1.7mm in its metal-shielded package. All that’s needed is to add a sensor, an antenna and a power source and you have a tiny, complete system for remote sensing and connection to the internet.
Using wireless modules to add quick and easy connectivity is not a new concept, but the increasing availability of module options to suit every need means there are fewer and fewer reasons to go down the discrete design route. Modules enable even brand new, emerging wireless technologies to be incorporated into designs without the need for specialist RF expertise. They optimise performance, footprint and cost, while minimising time to market, a winning formula for almost any type of design.