LMX1501 National Semiconductor, LMX1501 Datasheet - Page 18

• Manufacturer Part Number: LMX1501
• Description: PLLatinumTM 1.1 GHz Frequency Synthesizer for RF Personal Communications
• Manufacturer: National Semiconductor

Application Information
The reference spurious level is
filter attenuation and the low spurious noise level of the
LMX1511
The phase noise level at 150 Hz offset is
FIGURE 7 PLL Phase Noise
FIGURE 5 PLL Reference Spurs
k
b
66 dBc due to the loop
150 Hz Offset
(Continued)
b
75 5 dBc Hz
TL W 12340– 43
TL W 12340– 44
18
ure 8 shows the switching waveforms for a frequency jump
The phase noise level at 3 kHz offset is
Of concern in any PLL loop filter design is the time it takes
to lock in to a new frequency when switching channels Fig-
of 857 MHz– 915 MHz By narrowing the frequency span of
the HP53310A Modulation Domain Analyzer enables evalu-
ation of the frequency lock time to within
time is seen to be
FIGURE 6 PLL Phase Noise 3 5 kHz Offset
FIGURE 8 Frequency Jump Lock Time
k
1 6 ms for a frequency jump of 58 MHz
b
g
65 dBc Hz
1 kHz The lock
TL W 12340 – 45
TL W 12340 – 42