Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

PLL Phase Noise Analysis

Status
Not open for further replies.

4Ceesuns

Newbie level 4
Joined
Jan 4, 2015
Messages
5
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
46
When doing a PLL Phase noise analysis, I know reference noise within the loop BW is enhanced 20 log N, but in a digital PLL with a PFD, when the mfg supplies the noise floor or figure of merit, is the PN within the loop BW (enhanced) simply added to the phase detector noise, or is the phase detector noise also enhanced by 20*log N? Thanks in advance.
4Ceesuns
 

since the phase detector is running on some very low frequency, and the divider chain makes the oscillator track any tiny phase jump at the detector but making it N times bigger at the VCO output, yes the phase noise floor of the digital detector gets multiplied by 20 Log N
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top