LMX2594:LMX2594 ramp question

ko byeongguk

Other Parts Discussed in Thread: LMX2594, LMX2492

Hi, Ti

I have a question about the ramp function of the LMX2594.

I want to implement a chirp operation from 14 to 15 GHz within 100 µs using the LMX2594.

With a PFD of 100 MHz, would it be possible to achieve a performance level similar to the example in the datasheet, which shows a 125 MHz sweep over 100 µs?

5 months ago

+1 Noel Fung 5 months ago

TI__Guru** 111580 points

Hi There,

I used translator to understand your question.

Since your ramp range is 1GHz, multiple VCO calibration has to be taken during the ramp. As such, you will not get linear frequency ramp, and the total ramp time will be more than 100µs.

You will get something like below, because of VCO calibration in the middle of the ramp.

0 ko byeongguk 5 months ago in reply to Noel Fung

Prodigy 140 points

Hi Noel,

I'm really sorry — I was sure I wrote it in English, but it seems the browser's translation feature malfunctioned and ended up submitting it in Korean. I truly apologize for the confusion. It looks like going with the LMX2492 + VCO solution is the right choice.

0 Noel Fung 5 months ago in reply to ko byeongguk

TI__Guru** 111580 points

Hi There,

Correct, you need to use LMX2492 + external VCO.

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LMX2594:LMX2594 ramp question