CLRC663 -- LPCD I and Q values don't really make sense to me

[Julius_d]

Hi all,

I am currently trying to implement the CLRC66303hny frontend into a project I have been working on for a while. I am not using the NFC reader library but have built my own solution. Polling works perfectly well, LPCD mode on the other hand gives me a headache. 

When reading the I and Q values as described in AN11145 I get the values 0x00 and 0x40 from the two registers (0x42 and 0x43) and as far as I can see those can't be right and therefore can't be used for further calibrating the LPCD max/min values. Does anyone have an idea, how to approach this problem from here?

Im communicating with the IC over SPI, antenna should work well, so those aren't the problems. Is there anything I have to set before going into the IQ measurement routine?

Best regards, Julius

@Kan_Li I am tagging you since I know that you are the most likely to reply anyway! thanks in advance

[Julius_d]

on further investigation I noticed that I get two viable values when stepping through the code/delaying it - so maybe something with the working frequency of the chip itself?

[fangfang]

Hello,

One may refer to the application note for the more information.

URL:https://www.nxp.com.cn/docs/en/application-note/AN11783.pdf.

Hope it help you. Have a nice day.

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!
- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-----------------------------------------------------------------------------