Silicon Laboratories SI5375 User Manual

Page of 180
Si53xx-RM
Rev. 0.5
23
3.7.  Si5326
The Si5326 is a jitter-attenuating precision clock multiplier for applications requiring sub 1 ps jitter performance.
The Si5326 accepts dual clock inputs ranging from 2 kHz to 710 MHz and generates two independent,
synchronous clock outputs ranging from 2 kHz to 945 MHz and select frequencies to 1.4 GHz. The device provides
virtually any frequency translation combination across this operating range. The Si5326 input clock frequency and
clock multiplication ratios are programmable through an I
2
C or SPI interface. The DSPLL loop bandwidth is digitally
programmable from 60 Hz to 8 kHz, providing jitter performance optimization at the application level. Operating
from a single 1.8, 2.5, or 3.3 V supply, the Si5326 is ideal for providing clock multiplication and jitter attenuation in
high-performance timing applications. See "7. Microprocessor Controlled Parts (Si5319, Si5324, Si5325, Si5326,
Si5327, Si5367, Si5368, Si5369, Si5374, Si5375)" on page 76 
for a complete description. 
Figure 7. Si5326 Clock Multiplier and Jitter Attenuator Block Diagram
÷ N31
INT_C1B
Xtal or Refclock
÷ NC1
÷ NC2
Signal 
Detect
VDD
GND
C2B
0
1
f
3
CKOUT_2 +
CKOUT_2 –
CKOUT_1 +
CKOUT_1 –
/
/
2
2
1
0
1
0
f
OSC
RATE[1:0]
LOL
CS_CA
SDA_SDO
INC
DEC
RST
SCL
Control
SDI
A[2]/SS
A[1:0]
XA
XB
CMODE
CKIN_1 +
CKIN_1 –
2
     2
CKIN_2 +
CKIN_2 –
÷ N32
0
1
3
BYPASS
÷ N2
DSPLL
 ÷ N1_HS
DSPLL
®