LMX2571: Frequency switching by using TrCtl pin

Hiroshi Katsunaga

Mastermind 6480 points

Part Number: LMX2571

Hello,

My customer has a question about frequency switching by using TrCtl pin in LMX2571.

[Q]

Please tell me the right method of frequency swiching by using TrCtl.

I confirmed it by using EVM.

Low = F1

High = F2

However, it is described in the D/S as follows.

<D/S>

Switching is controlled by toggling the TrCtl pin.

Which is correct ?

Best Regards,

Hiroshi Katsunaga

over 5 years ago

0 Simon Damphousse over 5 years ago

TI__Expert 5370 points

Dear Hiroshi,

thank you for your question. I assigned your request and you will receive an answer shortly, thnak you for your patience.

Regards, Simon.

0 Noel Fung over 5 years ago in reply to Simon Damphousse

TI__Guru* 81400 points

Hi Katsunaga-san,

If you use TICS Pro with the EVM, the default output is F1 at RFoutRX port. If you want to use TrCtl to control F1 and F2 selection, do the following:

Change the F1/F2 Switch Control to Use TrCtl pin. When TrCtl_Pin is checked, RFoutTX will be selected using F2 register. If you want the output to be RFoutRX, then you should uncheck TX Enable and then check RX Enable.

0 Hiroshi Katsunaga over 5 years ago in reply to Noel Fung

Mastermind 6480 points

Hi Noel-san,

Thank you for your fast response.

However I have already known the contents of your comment.
I want to know the right description to control the frequency switching by using TrCtl pin.
Is description in D/S wrong?

<D/S (again)>
Switching is controlled by toggling the TrCtl pin.
~~~~~~~~~~

Best Reagards,
Hiroshi Katsunaga

0 Noel Fung over 5 years ago in reply to Hiroshi Katsunaga

TI__Guru* 81400 points

Hi Katsunaga-san,

As you know, If you have change the F1/F2 Switch Control to Use TrCtl pin, then F1 and F2 switching is controlled by TrCtl.
Toggling means making TrCtl pin High or Low. HIGH = TX while LOW = RX. It did not mean to make it High then Low.

0 Hiroshi Katsunaga over 5 years ago in reply to Noel Fung

Mastermind 6480 points

Hi Noel-san,

Thank you for your fast response and clear comment.

OK, I understood it.

Thank you for your cooperation.

Best Regards,
Hiroshi Katsunaga

Clock & timing

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LMX2571: Frequency switching by using TrCtl pin