Silicon Laboratories SI5351A/B/C Computer Hardware User Manual


 
Si5351A/B/C
Preliminary Rev. 0.95 19
5.4. Replacing Crystals, Crystal Oscillators, and VCXOs
The Si5351B combines free-running clock generation and a VCXO in a single package for cost sensitive video
applications. An example is shown in Figure 14.
Figure 14. Using the Si5351B to Replace Crystals, Crystal Oscillators, VCXOs, and PLLs
5.5. Replacing Crystals, Crystal Oscillators, and PLLs
The Si5350C generates synchronous clocks for applications that require a fully integrated PLL instead of a VCXO.
Because of its dual PLL architecture, the Si5351C is capable of generating both synchronous and free-running
clocks. An example is shown in Figure 15.
Figure 15. Using the Si5351C to Replace Crystals, Crystal Oscillators, and PLLs
Ethernet
PHY
USB
Controller
HDMI
Port
28.322 MHz
48 MHz
125 MHz
Video/Audio
Processor
74.25/1.001 MHz
24.576 MHz
OSC
XA
XB
CLK0
CLK1
CLK2
CLK3
CLK4
CLK5
PLL
VCXO
Multi
Synth
0
Multi
Synth
1
Multi
Synth
2
74.25 MHz
VC
27 MHz
Si5351B
Multi
Synth
3
Multi
Synth
4
Multi
Synth
5
Free-running
Clocks
Synchronous
Clocks
Note: F
BW
= 10 kHz
Ethernet
PHY
USB
Controller
HDMI
Port
28.322 MHz
48 MHz
125 MHz
Video/Audio
Processor
74.25/1.001 MHz
24.576 MHz
OSC
XA
XB
CLK0
CLK1
CLK2
CLK3
CLK4
CLK5
PLL
PLL
Multi
Synth
0
Multi
Synth
1
Multi
Synth
2
74.25 MHz
CLKIN
25 MHz
Si5351C
Multi
Synth
3
Multi
Synth
4
Multi
Synth
5
54 MHz
Free-running
Clocks
Synchronous
Clocks