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What is thermal noise called

wgtkan

Hello,

My cadence Virtuoso version is IC6.1.8-64b.500.9 and my Spectre simulator version is sub-version 19.1.0.237.isr3.

From my understanding sfl stands for the flicker noise of a transistor and what is the thermal noise? is it mn:sid? 

I read a note on this forum from long time ago:https://support.cadence.com/wps/mypoc/cos?uri=deeplinkmin%3AViewSolution%3BsolutionNumber%3D11018266 but I am not sure how to determine thermal noise.

Here is what I get for an N-channel and P-channel transistors mn and mp:

Total: 18 type(s) of signals
Signal type: V Data type: Real
'mn:vds' 'mn:vgs' 'mn:vsb' 'mn:vto' 'mn:vts' 'mn:vth' 'mn:vgt' 'mn:vdss' 'mn:vearly' 'mn:lp_vfb' 'mn:lp_a2' 'mn:vbs' 'mp:vds' 'mp:vgs' 'mp:vsb' 'mp:vto' 'mp:vts' 'mp:vth' 'mp:vgt' 'mp:vdss' 'mp:vearly' 'mp:lp_vfb' 'mp:lp_a2' 'mp:vbs' 'vbn' 'vbp' 'vdn' 'vdp' 'vgn' 'vgp' 'vx'
Signal type: I Data type: Real
'mn:1' 'mn:2' 'mn:3' 'mn:4' 'mp:1' 'mp:2' 'mp:3' 'mp:4' 'vbsn:p' 'vbsp:p' 'vdsn:p' 'vdsp:p' 'vgsn:p' 'vgsp:p' 'vnoi:p'
Signal type: enum Data type: Real
'mn:region' 'mp:region'
Signal type: real Data type: Real
'mn:sdint' 'mn:vsat' 'mn:u' 'mn:sfl' 'mn:sqrtsff' 'mn:sqrtsfw' 'mn:sid' 'mn:sig' 'mn:cigid' 'mn:noi_mid' 'mn:noi_mig' 'mn:noi_migid' 'mn:noi_cgeff' 'mn:noi_cigid' 'mn:fknee' 'mn:sigs' 'mn:sigd' 'mn:siavl' 'mn:ssi' 'mn:sdi' 'mn:lp_ct' 'mn:lp_themu' 'mn:lp_cs' 'mn:lv13' 'mn:lv14' 'mn:lp_thecs' 'mn:lp_ctg' 'mn:lp_cfac' 'mn:lp_axac' 'mn:lp_alpac' 'mn:lp_gc2ov' 'mn:lp_gc3ov' 'mp:sdint' 'mp:vsat' 'mp:u' 'mp:sfl' 'mp:sqrtsff' 'mp:sqrtsfw' 'mp:sid' 'mp:sig' 'mp:cigid' 'mp:noi_mid' 'mp:noi_mig' 'mp:noi_migid' 'mp:noi_cgeff' 'mp:noi_cigid' 'mp:fknee' 'mp:sigs' 'mp:sigd' 'mp:siavl' 'mp:ssi' 'mp:sdi' 'mp:lp_ct' 'mp:lp_themu' 'mp:lp_cs' 'mp:lv13' 'mp:lv14' 'mp:lp_thecs' 'mp:lp_ctg' 'mp:lp_cfac' 'mp:lp_axac' 'mp:lp_alpac' 'mp:lp_gc2ov' 'mp:lp_gc3ov'
Signal type: A Data type: Real
'mn:ise' 'mn:ige' 'mn:ide' 'mn:ibe' 'mn:ids' 'mn:idb' 'mn:isb' 'mn:igs' 'mn:igd' 'mn:igb' 'mn:idedge' 'mn:igcs' 'mn:igcd' 'mn:iavl' 'mn:igisl' 'mn:igidl' 'mn:ijs' 'mn:ijsbot' 'mn:ijsgat' 'mn:ijssti' 'mn:ijd' 'mn:ijdbot' 'mn:ijdgat' 'mn:ijdsti' 'mp:ise' 'mp:ige' 'mp:ide' 'mp:ibe' 'mp:ids' 'mp:idb' 'mp:isb' 'mp:igs' 'mp:igd' 'mp:igb' 'mp:idedge' 'mp:igcs' 'mp:igcd' 'mp:iavl' 'mp:igisl' 'mp:igidl' 'mp:ijs' 'mp:ijsbot' 'mp:ijsgat' 'mp:ijssti' 'mp:ijd' 'mp:ijdbot' 'mp:ijdgat' 'mp:ijdsti'
Signal type: Coul Data type: Real
'mn:qg' 'mn:qd' 'mn:qb' 'mn:qs' 'mn:qgs_ov' 'mn:qgd_ov' 'mn:qfgs' 'mn:qfgd' 'mn:qgb_ov' 'mn:qjun_s' 'mn:qjun_d' 'mp:qg' 'mp:qd' 'mp:qb' 'mp:qs' 'mp:qgs_ov' 'mp:qgd_ov' 'mp:qfgs' 'mp:qfgd' 'mp:qgb_ov' 'mp:qjun_s' 'mp:qjun_d'
Signal type: W Data type: Real
'mn:pwr' 'mn:pdiss' 'mp:pwr' 'mp:pdiss'
Signal type: Ohm Data type: Real
'mn:gm' 'mn:gmb' 'mn:gds' 'mn:gjs' 'mn:gjd' 'mp:gm' 'mp:gmb' 'mp:gds' 'mp:gjs' 'mp:gjd'
Signal type: F Data type: Real
'mn:cdd' 'mn:cdg' 'mn:cds' 'mn:cdb' 'mn:cgd' 'mn:cgg' 'mn:cgs' 'mn:cgb' 'mn:csd' 'mn:csg' 'mn:css' 'mn:csb' 'mn:cbd' 'mn:cbg' 'mn:cbs' 'mn:cbb' 'mn:cgsol' 'mn:cgdol' 'mn:cgbol' 'mn:cjs' 'mn:cjsbot' 'mn:cjsgat' 'mn:cjssti' 'mn:cjd' 'mn:cjdbot' 'mn:cjdgat' 'mn:cjdsti' 'mn:lv36' 'mn:lv37' 'mn:lv38' 'mp:cdd' 'mp:cdg' 'mp:cds' 'mp:cdb' 'mp:cgd' 'mp:cgg' 'mp:cgs' 'mp:cgb' 'mp:csd' 'mp:csg' 'mp:css' 'mp:csb' 'mp:cbd' 'mp:cbg' 'mp:cbs' 'mp:cbb' 'mp:cgsol' 'mp:cgdol' 'mp:cgbol' 'mp:cjs' 'mp:cjsbot' 'mp:cjsgat' 'mp:cjssti' 'mp:cjd' 'mp:cjdbot' 'mp:cjdgat' 'mp:cjdsti' 'mp:lv36' 'mp:lv37' 'mp:lv38'
Signal type: m Data type: Real
'mn:lpoly' 'mn:lv51' 'mp:lpoly' 'mp:lv51'
Signal type: Ohm Data type: Real
'mn:rout' 'mn:rg' 'mn:lp_rs' 'mp:rout' 'mp:rg' 'mp:lp_rs'
Signal type: A_V_2 Data type: Real
'mn:beff' 'mp:beff'
Signal type: Hz Data type: Real
'mn:fug' 'mp:fug'
Signal type: A_2_Hz Data type: Real
'mn:sfledge' 'mn:sidedge' 'mp:sfledge' 'mp:sidedge'
Signal type: m_2__V_s Data type: Real
'mn:lp_betn' 'mp:lp_betn'
Signal type: m_V Data type: Real
'mn:lp_mue' 'mp:lp_mue'
Signal type: V__1 Data type: Real
'mn:lp_xcor' 'mn:lp_thesat' 'mn:lp_thesatac' 'mp:lp_xcor' 'mp:lp_thesat' 'mp:lp_thesatac'
Signal type: K Data type: Real
'mn:dtsh' 'mn:tk' 'mp:dtsh' 'mp:tk'

  • These appear (from a bit of detective work) to be the operating point parameters from a psp103 (or related) model device. Note that these are not the noise contributions from a noise analysis, but just the operating point parameters describing how the model would behave under that bias point. The names of the parameters (and a short description) can be found in the output from "spectre -h psp103" in the Operating Points section, and there are equations related to the noise model in the psp103 chapter of the Spectre Circuit Simulator Components and Device Models Reference manual in the cdnshelp documentation in the SPECTRE stream (can also be found in <SPECTREinstDir>/doc/spectremod/spectremod.pdf )

    Note, it's always helpful to know in questions like this what type of device model you are talking about because the parameters are very different from one device to another.

    Regards,

    Andrew

  • in reply to Andrew Beckett

    Hello Andrew,

    Sorry for not mentioning the device model. You got it right. It is psp103 and I found this document on the web:

    https://www.nxp.com/wcm_documents/models/mos-models/model-psp/psp103p2_summary.pdf

    From there I see that: sfl or Sfl (1Hz) is the flicker noise current spectral density at 1Hz (A^2/Hz)

    sid or Sid is the channel thermal noise current spectral density at 1Hz (A^2/Hz)

    Thank you so much for your help. 

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