使用暫態分析模擬出phasenoise @ MMSIM701

gyamwoo

原文連結

以下原文內容：
) o3 T5 V0 F4 ^0 \: ]5 I
0 j# h6 S5 ?) g& xCalculating Large Signal Phase Noise Using Transient Noise Analysis
By Alan Whittaker on March 26, 2009

" K# [5 @- X* ?& S6 H! bMy name is Alan Whittaker and I'm in Cadence's Custom IC Proliferation Group.  
; b+ r+ X, C* oWe support Cadence's Technical Field Organization (the AEs) and Cadence customers
# X7 L$ j6 I9 n% f$ ^during the introduction and adoption of new and advanced EDA technologies.  I'll
. p& B3 n; `) n! A! T, Mbe posting here from time to time on methodologies and tool features that
0 F' }. U! s* x6 h, |+ O: bresolve issues that users have run into during the front-end analog, RF and
- _$ Z% c" j2 h4 Q% ^mixed-signal design process.
( d/ ~; M; W- t! M2 C1 u
I'm first going to address how you can perform a large-signal phase noise
analysis on a design block such as a VCO using our transient noise analysis
capability in our Spectre circuit simulator.  This approach is in addition to
! i+ ^" E9 m1 n* d3 T+ i8 a* Z  Hour small signal phase noise analysis which is available using either pnoise
or hbnoise analysis in the SpectreRF option to Spectre.
7 y6 |, @/ }# L
/ t7 k. J- T/ t4 n" N( l# K& wHere are the steps to obtain a phase noise plot from transient noise analysis:

& ?( U5 I& {7 p1.  Set up your oscillator testbench circuit for a transient noise analysis
(See sourcelink for the Transient Noise appNote - it doesn't discuss the phase
  E$ U2 r+ P# h- z+ bnoise measurement, but describes how to properly set up the simulation analysis
' J* T+ e# W9 d4 C  T
( C; D* S) W6 v2.  Add the block freq_meter from the pllMMLib library
($CDSHOME/tools//dfII/samples/artist/pllMMLib)
to the testbench circuit. Important: The instance name for this block must be
'vco_freq'.
# ?6 [" C  Z; c7 l( {0 Y
- W8 X1 R6 U# p" N0 JIf the oscillator output is differential, connect it to the vin_p and vin_n
pins on the freq_meter block. If the oscillator output is single ended, connect
it to the vin_p pin and connect the vin_n pin to ground. Connect a noConn cell
, q% {- M2 I) B. l" hfrom the basic library to the out_freq pin.

gyamwoo

The parameters for this block are (set Tools Filter to veriloga in the CDF
parameter form:
  w" l% w( u' N& @, m5 C    *
3 A2 }; I2 l4 v8 {6 m      Vthup: Threshold voltage to determine the rise edge of the input waveform.
7 P) B3 \* P& t/ u9 I, [, HThe input waveform period is determined by two adjacent rise edges. Default is 0.
    *
3 w0 Z- b- {0 n4 C/ G$ ~      ttol: The tolerance of the time where the rise edge is determined. Default
is 1p.
/ ^/ k% |2 [: w$ p; W- j4 o: ^    *
      outStart: The time-dependent period of the input waveform is output to the
file when the time is greater than outStart. Default is 0. To get accurate phase
# E0 M' Y! Q  @6 `, X0 anoise measurements, set this to past the time when the oscillator is fully
1 z6 j/ }# p8 J9 {powered up and oscillating at the design frequency.
, y0 a' T. ^. s6 m  T1 J" z    *
( q5 r* v( R: C      outfile: The name of a file to contain time-dependent periods for use in
later psd calculations. Specify just the file name, not a path. If outfile is
" U1 _9 L  L/ D9 q/ a+ lleft blank, the default name is periods.txt.

gyamwoo

3.  Before starting the simulation, in the ADE window, Select Tools->RF->LL. In the PLL Macro Model Wizard window, enable PLL Macro Model and select PLL Bench as the Bench Type. Then OK this form.

1 h/ u: F4 g' z2 {& d4.  Run the simulation. The simulation must run successfully to completion in order to get to the phase noise results.
+ ~: X( S+ ~4 r% @4 l8 ~! _
/ t: r8 Y; I! S( F5 D5.  In the Direct Plot form for transient noise there should be a PLL PSD Noise option. This will allow you to plot the phase noise results. If a message appears saying that the PLL Noise PSD data is not available, check steps 3) and 4). If you make any corrections, you will need to re-run the simulation.
0 ?1 O9 W! |' `- d0 T
The phase noise plot will extend from fmin = 4/tstop to fmax = fosc/2, where tstop is the transient noise simulation stop time and fosc is the oscillation frequency of the circuit.
" c; u% [$ h- }0 C  f
Important note: You will need to use MMSIM701 and IC5141USR5 or IC613 (or latersubversions) to obtain a phase noise plot from transient noise analysis.

& M2 n2 g4 Z; H( c3 _1 p我用的是mmsim620，也不能模。有人可以模擬出來的回個文，show個圖給大家看吧

macrohan

show you my simulation result
!!!
; O& J: o4 U6 R4 D5 z!!!!!!!!!!!
!!!!!!

gyamwoo

謝謝你的回覆，我最近拿到新的軟體也開始在測試mmsim7了
我發現turbo與multi thread的設定不同會對結果造成很大的不同。
還有這個phase noise的訊號的範圍跟transient noise的設定與transient 的設定都有很緊密的關係。
不知道該怎麼作設定才是比較準確的

kunhsun

請問有更詳盡的使用方法嗎

duoyun

也去试试这个流程。关于pll相噪仿真还有其他方法吗？