RFID IC with energy harvesting, user data, wake-up signal to MCU

[angus123]

Hi There,

I am developing a product where I need to remotely wake up my electronics from 0.5-1.5 m, and also read back some user information about the unit I just woke up (e.g. serial number, firmware version the MCU is running etc). It needs to be as low power draw as possible while asleep.

I was thinking that RFID could be a good candidate for this, with an IC that can harvest RF energy to output a signal (gpio or just output voltage/current based on harvested energy) that I can use to wake my MCU. It can also send back user data to the scanner such as firmware version and serial data. Given my range, I was thikning that UHF is the most appropriate (correct me if I am wrong here).

Does STM have any products that suit my needs? I was looking at the STM25DV04KC, however being in the HF range, I am concerned I will not get the range that I require. If it could, what size of antenna would I require to get 0.5-1.5m wake range? If it cant, do you have any other recommendations?

Thanks in advance :)

[Berenice BENVEGUDA · Accepted solution]

Hello @angus123 

First of all thanks for your interest for ST25 product family !

Then, additional details abut your use case/system capability would be necessary to advise you.

Nevertheless, in a first approach, to have a chance to reach such detection distance, at reader side an antenna size  in the range of 80x60 cm providing a power of several watts, and at tag side  an antenna in the range of a credit card at least would be necessary.

ST25DV04KC could be a candidate with its GPO configured as wake up interrupt.

I hope this helps,

Best Regards,

BB

[angus123]

Hi Berenice,

As I suspected, those are far too large for my application. I need to use UHF to reach my required range while remaining small enough to be practical, which ST unfortunately does not provide. Thanks for your help!