Si53xx-RM
Rev. 0.5 119
APPENDIX A—NARROWBAND REFERENCES
Resonator/External Clock Selection
Table 59 shows the 114.285 MHz third overtone crystals that have been approved for use with the Si53xx jitter
attenuating clocks.
In some applications, a crystal with frequencies other than 114.285 MHz may be used. Contact Silicon Labs for
details and a current list of crystal vendors and approved part numbers.
External reference (and crystal) frequency values should be avoided that result in an output frequency that is an
integer or near integer multiple of the reference frequency. See Appendix B for details.
Because the crystal is used as a jitter reference, rapid changes of the crystal temperature can temporarily disturb
the output phase and frequency. For example, it is recommended that the crystal not be placed close to a fan that
is being turned off and on. If a situation such as this is unavoidable, the crystal should be thermally isolated with an
insulating cover.
Table 59. Approved Crystals
Manufacturer Part Number Web Site Stability Initial
Accuracy
TXC 7MA1400014 http://www.txc.com.tw 100 ppm 100 ppm
Connor Winfield CS-018 http://www.conwin.com 100 ppm 100 ppm
Connor Winfield CS-023 http://www.conwin.com 20 ppm 20 ppm
NDK EXS00A-CS00871 http://www.ndk.com/en/ 100 ppm 100 ppm
NDK EXS00A-CS00997 http://www.ndk.com/en/ 20 ppm 20 ppm
Siward XTL573200NLG-
114.285 MHz-OR
http://www.siward.com 20 ppm 20 ppm
Saronix/eCera FLB420001 http://www.pericom.com/saronix
http://www.ecera.tw
100 ppm 100 ppm
Mtron M1253S071 http://www.mtronpti.com 100 ppm 100 ppm
Table 60. XA/XB Reference Sources and Frequencies
RATE[1:0] NB/WB Type Recommended Lower limit Upper limit
HH WB No crystal or external clock — — —
HM NB Reserved — — —
HL NB Reserved — — —
MH NB External clock 114.285 MHz 109 MHz 125.5 MHz
MM NB 3rd overtone crystal 114.285 MHz — —
ML NB Reserved — — —
LH NB Reserved — — —
LM NB External clock 38.88 MHz 37 MHz 41 MHz
LL NB Fundamental mode crystal 40 MHz 37 MHz 41 MHz