
6.1.1 DCO with Frequency Increment/Decrement Pins/Bits
. . . . . . . . . . . . . . .34
6.1.2 DCO with Direct Register Writes
. . . . . . . . . . . . . . . . . . . . . .34
6.2 Using the M Divider for DCO Applications . . . . . . . . . . . . . . . . . . . . .34
7. Dynamic PLL Changes. . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 Revisions B and A . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
7.2 Revision D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
7.3 Dynamic Changes to Output Frequencies without Changing PLL Settings . . . . . . . . . .36
7.4 Dynamic Changes to Output Frequencies while Changing PLL Settings Using a CBPro Register
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
8. Serial Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
8.2 SPI Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
9. Field Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10. Recommended Crystals and External Oscillators . . . . . . . . . . . . . . . .
11. Crystal and Device Circuit Layout Recommendations. . . . . . . . . . . . . . .
11.1 64-Pin QFN Si5341 Layout Recommendations
. . . . . . . . . . . . . . . . . .46
11.1.1 Si5341 Applications without a Crystal
. . . . . . . . . . . . . . . . . . . .46
11.1.2 Si5341 Crystal Layout Guidelines . . . . . . . . . . . . . . . . . . . . . .47
11.1.3 Output Clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
11.2 44-Pin QFN Si5340 Layout Recommendations . . . . . . . . . . . . . . . . . . .52
11.2.1 Si5340 Applications without a Crystal as the Reference Clock . . . . . . . . . . . .52
11.2.2 Si5340 Crystal Guidelines . . . . . . . . . . . . . . . . . . . . . . . .53
12. Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.1 Power Management Features . . . . . . . . . . . . . . . . . . . . . . . .56
12.2 Power Supply Recommendations . . . . . . . . . . . . . . . . . . . . . . .56
12.3 Grounding Vias . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
. . . . . . . . . . . . . . . . . . . . . . . . .57
13. Base vs. Factory Preprogrammed Devices . . . . . . . . . . . . . . . . . . .
13.1 “Base” Devices (Also Known as “Blank” Devices) . . . . . . . . . . . . . . . . . .58
13.2 Factory Preprogrammed (Custom OPN) Devices . . . . . . . . . . . . . . . . . .58
14. Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14.1 Register Map Overview and Default Settings Values . . . . . . . . . . . . . . . . .59
14.2 Si5341 Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . .59
14.2.1 Page 0 Registers Si5341. . . . . . . . . . . . . . . . . . . . . . . . .60
14.2.2 Page 1 Registers Si5341. . . . . . . . . . . . . . . . . . . . . . . . .69
14.2.3 Page 2 Registers Si5341. . . . . . . . . . . . . . . . . . . . . . . . .73
14.2.4 Page 3 Registers Si5341. . . . . . . . . . . . . . . . . . . . . . . . .79
14.2.5 Page 9 Registers Si5341. . . . . . . . . . . . . . . . . . . . . . . . .82
14.2.6 Page A Registers Si5341
. . . . . . . . . . . . . . . . . . . . . . . .83
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
3
Rev. 1.3 • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • July 26, 2021
3