RC66302 LPCD I-Result value

[MIMIwho]

当我在使用RC6602的LPCD模式时，设置Imin = 1，Imax=0x3F，当执行一次LPCD 后，获取LPCD_RESULT_I寄存器的值，当前值为0x43，超出了解释范围，该怎么理解这个溢出的位，后续的LPCD的I值应该怎么设置呢？

[EduardoZamora]

Hello @MIMIwho

Hope you are doing well.

Please, consider that CLRC66302 is Not Recommended for New Designs, we recommend using CLRC663 plus family.

Bits 7 to 6 of LPCD_Result_I (address 42h) are RFU. Result of the last low-power card detection (I-Channel) is shown in bits 5 to 0.

By any chance, have you followed AN11145 CLRC663, MFRC631, MFRC 630, SLRC610 Low Power Card Detection? This document describes the principle of LPCD, its usage and how to optimize related settings.

Regards,
Eduardo.

[MIMIwho]

Thank you ,I will check back!
I have another question:
When I start the LPCD once ,then I get the LPCD_Result_I(address 42h) register value, the value is 0,Is that normal？What can I do to make the I-Channel value is not the zero? Because I found ,if the I-Channel value equals 0 ，Modules are more easily awakened.

[EduardoZamora]

Hi,

What is the procedure you are following to configure LPCD? Please make sure you are following the LPCD calibration procedure described in AN11145 CLRC663, MFRC631, MFRC 630, SLRC610 Low Power Card Detection, Section 3.2.

Regards,
Eduardo

[MIMIwho]

I am following the LPCD calibration procedure described in AN11145 CLRC663, MFRC631, MFRC 630, SLRC610 Low Power Card Detection, Section 3.2.1 Reading I and Q value.

But the result of I is zero,and the result of Q is not zero, Is that normal? What can I do to fix this problem?

[EduardoZamora]

Hi,

Just to confirm, are you using a custom board based on RC66302 (NRND)? If so, have you performed proper antenna tuning according to AN11019?

Regards,
Eduardo.

[MIMIwho]

YES,I used the RC66302 .

And I think I am performed proper antenna tuning,and The PCD antenna size is 33mm×48mm rectangle，Can you provide me with a reference parameter？

[EduardoZamora]

Hi,

Using CLEV6630 (65mm x 65mm antenna) and NFC Cockpit, I obtain Result_I x2A and Result_Q 0x14.

Could you please provide the Smith Chart of your setup?

Regards,
Eduardo.