8
SNAU137
LMX248x Evaluation Board User’s Guide
Revised - March 2014
Copyright © 2014, Texas Instruments Incorporated
IF LOOP FILTER
Theoretical ( NOT Measured ) Simulation ( Done with EasyPLL at www.ti.com )
Phase Margin
47.1 deg
Lock Time
760 - 780 MHz
MHz to 1 KHz
tolerance in 453
uS
Loop Bandwidth
5.1 KHz
Spur Gain
@ 200 KHz
22.1 dB
VCO
CPoRF
1.8 nF
10 nF
8.2 K
Ω
Open
Open
0
Ω
0
Ω
Settings for Operation
K
φ
4 mA
Comparison
Frequency
50 kHz
Output
Frequency
760 - 780 MHz
PLL Supply
2.5 Volts
VCO Supply
3 Volts
Other Information
VCO Used
VARIL191-773U
VCO Gain
18 MHz/Volt
VCO Input
Capacitance
100 pF