1, Use a low-noise, high-PSRR LDO regulator to power the external oscillators used to drive the XO and TCXO
inputs. Typically, oscillator jitter performance is typically impacted by switching noise on its power supply.
2,
Power supply Filtering is used to
.Reduce the noise on the power supply rail from entering the sensitive blocks
.Maximize isolation between circuitries on the same device
Multiple VDDO pins can share a filtered supply when OUTs are the same frequency.
Choose FB with some DCR
.Reduces Q of LC filter, ZAC . 220 ohm @ 100 MHz, and DC current rating >2x above expected max current
.Consider small damping resistor in series with large cap to mitigate LC resonant peaking
Add multiple bypass cap value(s) to filter other known noise frequencies, especially if in the noise bandwidth of interest.
3, LMK05028 internal LDOs also have some noise suppression. If clock jitter/phase noise is sensitive in user's application, a low noise, high-PSRR LDO with enough current capability is recommended, like XO supply.
