3 Typical Measurement
3.1 Default Configuration
3.1.1 Loop Filter
The parameters for the loop filter are shown in
Table 3-1. Loop Filter Configuration
PARAMETER
VALUE
VCO frequency
Designed for 4.8 GHz, but works
over the whole frequency range
VCO gain
56 MHz/V
Effective charge pump gain
2500 µA
Phase detector frequency
80 MHz
Loop bandwidth
205 kHz
Phase margin
40 degrees
C1_LF
390 pF
C2_LF
4.7 nF
R2_LF
680 Ω
R3_LF = R4_LF (Internal)
800 Ω
C3_LF (Internal)
50 pF
C4_LF (Internal)
100 pF
Figure 3-1. Loop Filter
3.1.2 Typical Output
1. Follow
2. Click
Write All Registers
to write all the registers to LMX2571-EP. The default output is 480 MHz.
Figure 3-2. Default Output
Typical Measurement
6
LMX2571EPEVM Evaluation Instructions
SNAU182 – MARCH 2021
Copyright © 2021 Texas Instruments Incorporated
