Other Parts Discussed in Thread: LMX2820, , LMX2694-EP, LMX2594
Tool/software: WEBENCH® Design Tools
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Many of these questions refer to the Pllatinum Simulator
1. When I run the Pllatinum simulator, what is the lock time (frequency settling) for full assisted calibration? I am thinking I have to include VCO cal table and partial assist, is that right?
2. In lock time in the simulator, how does discrete lock time model differ from Analog lock time?
3. Is there any documentaton on the simulator that answers the above and other questions?
4. I need to operate just slightly below 19 GHz but would like to operate slightly above 85C. Is an EP suffix planned for this part?
5. What degradation could be assumed up to a 100C case temperature?
6. Would the LMX2820 be a better choice for me?
7. What does MASH stand for and what does it mean? Appears to mean fractional.
8. Will a single VCO calibration work over the entire temperature range?
9. The simulation shows a phase detector spur in the range of -60 to -80 dBc (200 MHz fractional PFD). Analog Devices parts show a much lower spur (e.g. ADF4371). Is there anything that can be done to reduce this spur? Will more loop filtering help or not? Is it really that high? 1
10. What are S1, S2 and S3 in the simulator?
11. How do I pick the VCO for the LMX2595 in the simulation? It lets me pick any VCO for any frequency, isn't this wrong?
12. The simulator does not seem to account for the internal X2 of the LMX2595, is there a way to include this?