the tuning frequency of an M24SR?

[thao]

Posted on March 03, 2014 at 16:12

Dear everybody

I have read about ''Using the same antenna for M24LRXXE-R and M24SRXX-Y'' in document AN4409. It describes in table 2.''Tuning parameters for M24LRXXE-R and M24SRXX-R'', that the tuning frequency of an M24SRXX is 14MHz-14.4MHz. But fc in datenblatt (page75) is only 13.55Mhz - 13.56Mhz.With which frequency can I design the antenna for the M24SR? Do you have any notes for the calculating the antenna for the M24SR? I only find the documents for the M24LRThank you and best regards #frequency-tuning #m24lr #m24sr

[Anais GALLIGANI · Accepted solution]

Posted on March 04, 2014 at 17:25

Hello,

The tuning frequency for M24SR is between 14Mh and14.4Mhz

Page 75 of the datasheet does not refer to any tuning frequency, could you please download the latest one at

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00067892.pdf

.

Page 76, in table 82, fc parameter refers to the tolerance of RF carrier wave generated by the RFID or NFC reader. The tuning frequency of reference tag used for product qualification is 14.2MHz, as mentioned in note 1.

Antenna design procedure is the same for M24LR and M24SR because both product have been design to use the same antenna. tuning frequency difference recommended in AN4409 is satisfied by the different internal tuning capacitance value inside M24LR and M24SR family.

I hope this is helping,

Have a nice day, ST NFC/RFID Dynamic tag support