NTM88 433MHz RF output impedance matching circuit

[arjansplit]

Dear all,

Currently i'm working on a design which incorporates the NTM88 TPMS sensor. Due to the obsolesce of the FTXH87 series I'm changing towards the NTM88 sensor. However as where it is mentioned in the documentation of the FTXH87 series, I cannot find any information with regards to the output impedance requirements of the NTM88 RF 433MHz output.

I've found in the User manual a schematic drawing, however no component value's are mentions.

I've found the X-TPMS88EH11S434 schematic, but here no component value's are given. (https://www.nxp.com/webapp/Download?colCode=SPF-29825-A2)

So is there anyone who could help me with determining the correct circuit and component value's for matching the RF output to 50Ohm at 433MHz?

Best regards,

Arjan Split

[TomasVaverka · Accepted solution]

Dear Arjan,

Please find attached three documents. One refers to the schematic of our reference design with component values indicated on it, another one is the dimension of antenna used on this reference design (a simple clip of metal, let’s say steel stainless), and the last one, the most important, describes the impedance to target at the RF pin (or in practice, at the SMA connector plane).

I hope it helps.

Best regards,

Tomas

[arjansplit]

Hi Tomas,

Thank you very much for your response. The documentation that you've provided was exactly what I was looking for.

Thanks and until next time!

Arjan Split