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Typical Measurement
9
SNAU217A–August 2017–Revised November 2017
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LMX2572EVM Evaluation Instructions
3.2.3 Automatic Ramping
This ramping mode supports wider ramp frequency, however there are glitches in the middle of the ramp
because of VCO calibrations which are required so as to ensure the continuity of the ramp.
Table 4. Automatic Ramp Example
PARAMETER EXAMPLE VALUE
Ramping start frequency 4740 MHz
Ramping stop frequency 4860 MHz
Phase detector frequency 50 MHz
Ramp up / down time 1000 µs
RAMP_LIMIT_HIGH 5060 MHz
RAMP_LIMIT_LOW 4540 MHz
f
OSCin
100 MHz
CAL_CLK_DIV 0
RAMP_THRESH 40 MHz
Pause time for VCO calibration 500 µs
Figure 11. Automatic Ramp Setting
Figure 12. Automatic Ramp