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  3. noise analysis with cds_srr

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noise analysis with cds_srr

itos
itos over 9 years ago

Hi again ;-)

I have problems loading noise results with cds_srr:

>> struct_n = cds_srr(c.outfile, 'sweepvds_noisen-sweep', 'out')
Error using  .'
Transpose on ND array is not defined.

Error in cds_srr (line 38)
      eval(sprintf('sig.%s = sig.%s.'';', char(sig.info(1)), char(sig.info(1))));

>> struct_n = cds_srr(c.outfile, 'sweepvds_noisen-sweep', 'in')
Error using  .'
Transpose on ND array is not defined.

Error in cds_srr (line 38)
      eval(sprintf('sig.%s = sig.%s.'';', char(sig.info(1)), char(sig.info(1))));

Both signals exist:

>> struct_n = cds_srr(c.outfile, 'sweepvds_noisen-sweep')
Total: 25 properties
     'PSFversion'      'BINPSF creation time'      'PSF style'      'PSF types'      'PSF sweeps'      'PSF sweep points'      'PSF sweep min'      'PSF sweep max'      'PSF groups'      'PSF traces'      'simulator'      'version'      'date'      'design'      'analysis type'      'analysis name'      'analysis description'      'xVecSorted'      'tolerance.relative'      'operating point producer'      'output'      'ground'      'positive output signal'      'negative output signal'      'input probe'

Total: 2 type(s) of signals
Signal type: V_sqrt_Hz_    Data type: Real
     'out'      'in'
Signal type: V_V    Data type: Real
     'gain'


struct_n =

    signal_info: {'prop'  'Unknown'  'V_sqrt_Hz_'  'Real'  'V_V'  'Real'}
           prop: {25x1 cell}
     V_sqrt_Hz_: {2x1 cell}
            V_V: {'gain'}

I used now the newest software which is installed on the system: MATLAB 2012b 64 bit, MMSIM14.10.826.lnx86 (both spectre and toolbox). Problem persists also in older versions.

The noise is within a double sweep analysis (vds and vgs) and the statements are:

noisen (vonn 0) noise freq=1G iprobe=vgsn
noisep (vonp 0) noise freq=1G iprobe=vgsp

Thank you!

EDIT: This seems to be a bug indeed that occurs when only one frequency is chosen. As a workaround:

noisen (vonn 0) noise start=1G stop=2G lin=1 iprobe=vgsn
noisep (vonp 0) noise start=1G stop=2G lin=1 iprobe=vgsp

to generate 2 frequency data points

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  • Andrew Beckett
    Andrew Beckett over 9 years ago

    I've not found this reported before.

    Any chance you can post your netlist (with the circuit and sweep statements etc) to avoid me having to guess what you've done? No need for the models - I can invent those.

    Thanks,

    Andrew.

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