Other Parts Discussed in Thread: , LMX2572, LMX2492
We're using the LMX2594 + Reference Pro + TICS Pro (1.6.10) to understand the ramp function within the device. While we can generate ramps, there appear to be frequencies outside the desired band.
Using the settings from the LMX2594 EVM Manual, figure 18 (generating a calibration-free ramp between 12.000 and 12.125GHz).
Settings on PLL page ...
And settings on ramp page ....
(Ramp is disabled) Produces 6.0GHz as expected (note that channel divider set at 2 to bring output within the range of Tek RSA306) ...
Ramp is now enable by simply checking the box on the TICS ramp page ...
Outputs ramp is generated (see below) however, the response is not flat, and there is an additional 5.25MHz below the 6.000GHz (the expected ramp extending between 6.0000 and 6.0625GHz).
1. Do these setting appear correct for a calibration-free 125MHz (at the VCO) ramp?
2. What might we be missing that could explain the plot below?
3. During VCO calibration, what should be expected at an enabled RFout?
Thanks ... Jim