Can sensor tags shrink in size as much as standard RFID tags have? Miniaturization is a trend in all electronics that has an impact in the sensor tag market of course.

As discussed in our previous post, using less and smaller electronics is desirable for manufacturers ourselves for obvious cost effectiveness.

However, there is another reason as important as the cost itself: size constrains of applications.

RMeter miniaturization example

RMeter resistance value monitoring sensor miniaturization example

The picture shown is an example of the same product using a single side or both sides of the PCB for the assembly. The size reduction is obvious. It also shows the change from a long dipole antenna versus a shorter design. Communication range drops from over 1.5 meters to around half a meter.

In order to reduce size of RFID sensor tags you may work on different areas:

Tag antenna

Tag antenna is one of the obvious components to work with. Compared with the rest of electronics – a single die in the case of standard RFID, many components in case of sensor tags – the antenna usually is very big.

On the other side, changing the antenna design directly impacts the RFID system performance. In general, the smaller the antenna, the shorter the communication range. That is a tradeoff you will eventually have to take a decision on.

This previous post explains how antenna size impacts the read range of our sensor tags based on results using different commercial antennas.

Semiconductor integration

You can also work on integration of discrete electronics inside the RFID chip. Embedding functionalities of the external components into the RFID chip will make the chip a little bit larger while greatly reducing the substrate area required for the circuitry.

While it may seem like a great idea, integration is a hard task, it is expensive and generally linked to high volumes of sales for that specific product.

Note that it will also affect the performance in two ways:

  • It will probably perform better for the application you developed the specific integration.
  • It will probably perform worse for other applications you were using the same chip. You introduced extra circuitry in the chip that was not required so both performance and cost will be worse.
Wafer with RFID chip dies

Wafer with Farsens’s RFID chip dies

Circuitry miniaturization

Trying to shrink the designs to their minimum is the third area of work. For a given product design, you can always reduce its size – at a cost that is directly proportional to the level of miniaturization required.

From using two sides of the substrate to reduce the size of the components used, there are a myriad of ways to approach miniaturization.

Reducing size of RFID sensor tags is possible in different ways the same way you can work on miniaturization of any other electronics. You just need to make sure you can take on the tradeoffs in terms of cost and performance.