3.3 Fault Monitoring
All four input clocks (IN0, IN1, IN2, IN3) are monitored for loss of signal (LOS) and out-of-frequency (OOF) as shown below. The refer-
ence at the XA/XB pins (grades A/B/C/D/P) or the integrated reference (grade J/K/L/M/E) are monitored for LOS because it provides a
critical reference clock for the DSPLLs. There is a loss of lock (LOL) indicator asserted when the DSPLL loses synchronization with its
reference input.
DSPLL
LPF
PD
÷M
IN0
IN0
Precision
Fast
OOF
LOS
÷P
0
IN1
IN1
Precision
Fast
OOF
LOS
÷P
1
IN3/FB_IN
IN3/FB_IN
Precision
Fast
OOF
LOS
÷P
3
IN2
IN2
Precision
Fast
OOF
LOS
÷P
2
LOL
XB
XA
OSC
LOS
÷5
Figure 3.4. Si5386 Fault Monitors
Si5386 Rev. E Reference Manual • Clock Inputs
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
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Rev. 1.2 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • December 9, 2021
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