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PSS analysis for 0.13um CMOS LNA design suddenly stop at 10 percent

Hye, i am currently working on a design of LNA in 0.13um CMOS. Im done with s parameter and NF part and now Im trying to obtain a result from pss analysis for 1db compression Point and and IIP3. The bandwidth of this LNa is starting from 3G to10G hz. When Im doing the PSS analysis, its suddenly stop at 10 percent of iteration, meaning to say if we give the prf variable staring from -40 dBm to 0 dBm it only run until -36 dBm and the condition on ADE is turn to ready.

Please kindly help me. have try so many thing but nothing seems to work. really needs help here.
together with this thread im attached the screeshot of the output log,properties of input port, and pss analysis setting.

Andrew Beckett over 9 years ago

First of all, please post the entire spectre.out file as an attachment (using the Upload Media button - you might have to change the file suffix) so we can see precisely how it fails. That will also give more information about the version of the simulator you're using (clearly you're running IC5141 ADE, but I'm more concerned about the spectre version). It will also give useful info about the size of the circuit too, simulator accuracy settings and so on - you've cropped so much out that it's almost impossible to tell what you've done.

Your setup is a bit odd too. The PSS form says that the frf fundamental is 4.5G yet you've set the PSS fundamental to 450MHz. Why? There's no point in including a subharmonic unless there's a divider somewhere (which seems unlikely). So leave the fundamental at 4.5GHz.

Regards,

Andrew
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encik RFIC over 9 years ago

here is the Mr Andrew Beckett. I hope you can help me

Fullscreen spectre.out.txt Download

Command line:
    /cadence/MMSIM60USR2/tools.lnx86/spectre/bin/32bit/spectre -env  \
        artist5.1.0 +escchars +log ../psf/spectre.out +inter=mpsc  \
        +mpssession=spectre0_7868_45 -format sst2 -raw ../psf  \
        +lqtimeout 900 -maxw 5 -maxn 5 input.scs
spectre pid = 14766

Loading /cadence/MMSIM60USR2/tools.lnx86/cmi/lib/4.0/libinfineon_sh.so ...
Loading /cadence/MMSIM60USR2/tools.lnx86/cmi/lib/4.0/libnortel_sh.so ...
Loading /cadence/MMSIM60USR2/tools.lnx86/cmi/lib/4.0/libphilips_sh.so ...
Loading /cadence/MMSIM60USR2/tools.lnx86/cmi/lib/4.0/libsparam_sh.so ...
Loading /cadence/MMSIM60USR2/tools.lnx86/cmi/lib/4.0/libstmodels_sh.so ...
spectre (ver. 6.0.2.119 -- 10 Nov 2005).
Includes RSA BSAFE(R) Cryptographic or Security Protocol Software from RSA Security, Inc.

Simulating `input.scs' on CEDECUSMEE at 4:57:34 AM, Wed May 25, 2016.
Using new Spectre Parser.
Auto-loading AHDL component.
Finished loading AHDL component in 0 s (elapsed).
Installed AHDL simulation interface.
Opening directory input.ahdlSimDB/ (770)
Opening directory input.ahdlSimDB/input.ahdlcmi/ (770)
Installed compiled interface for bsource_1.
Installed compiled interface for bsource_2.
Installed compiled interface for bsource_3.
Installed compiled interface for bsource_4.
Installed compiled interface for bsource_5.
Installed compiled interface for bsource_6.
Installed compiled interface for bsource_7.
Installed compiled interface for bsource_8.
Installed compiled interface for bsource_9.
Installed compiled interface for bsource_10.

Circuit inventory:
              nodes 15
          equations 48
              bsim4 4     
          capacitor 4     
              diode 4     
           inductor 5     
               port 2     
           resistor 2     
            vsource 4     

Entering remote command mode using MPSC service (spectre, ipi, v0.0, spectre0_7868_45, ).

*******************************************
Sweep Analysis `sweeppss': prf = (-40 -> 0)
*******************************************

+++++++++++++++++++++++++
sweeppss: prf = -40 (0 %)
+++++++++++++++++++++++++

*****************************************************************
Periodic Steady-State Analysis `sweeppss-000_pss': fund = 4.5 GHz
*****************************************************************
Trying `homotopy = gmin' for initial conditions.

==============================================
`sweeppss-000_pss': time = (0 s -> 222.222 ps)
==============================================
Important parameter values in tstab integration:
    start = 0 s
    outputstart = 0 s
    stop = 222.222 ps
    period = 222.222 ps
    step = 222.222 fs
    maxstep = 8.88889 ps
    ic = all
    skipdc = no
    reltol = 1e-03
    abstol(I) = 1 pA
    abstol(V) = 1 uV
    temp = 27 C
    tnom = 27 C
    tempeffects = all
    method = traponly
    lteratio = 3.5
    relref = sigglobal
    cmin = 0 F
    gmin = 1 pS
    maxrsd = 0 Ohm
    mos_method = s
    mos_vres = 50 mV

    sweeppss-000_pss: time = 6.889 ps     (3.1 %), step = 3.556 ps      (1.6 %)
    sweeppss-000_pss: time = 22.89 ps    (10.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 31.78 ps    (14.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 40.67 ps    (18.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 58.44 ps    (26.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 67.33 ps    (30.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 76.22 ps    (34.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 85.11 ps    (38.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 102.9 ps    (46.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 111.8 ps    (50.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 120.7 ps    (54.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 129.6 ps    (58.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 147.3 ps    (66.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 156.2 ps    (70.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 165.1 ps    (74.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 174 ps      (78.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 191.8 ps    (86.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 200.7 ps    (90.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 209.6 ps    (94.3 %), step = 8.889 ps        (4 %)
    sweeppss-000_pss: time = 222.2 ps     (100 %), step = 6.333 ps     (2.85 %)
Conv norm = 2.46e+03, max dI(V1:p) = 268.494 uA, took 10 ms.

Important parameter values in pss iteration:
    start = 0 s
    outputstart = 0 s
    stop = 222.222 ps
    period = 222.222 ps
    steadyratio = 1e-03
    step = 222.222 fs
    maxstep = 1.11111 ps
    ic = all
    skipdc = no
    reltol = 1e-03
    abstol(I) = 1 pA
    abstol(V) = 1 uV
    temp = 27 C
    tnom = 27 C
    tempeffects = all
    errpreset = moderate
    method = gear2only
    lteratio = 3.5
    relref = alllocal
    cmin = 0 F
    gmin = 1 pS
    maxrsd = 0 Ohm
    mos_method = s
    mos_vres = 50 mV


==============================================
`sweeppss-000_pss': time = (0 s -> 222.222 ps)
==============================================
    sweeppss-000_pss: time = 5.556 ps     (2.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 16.67 ps     (7.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 27.78 ps    (12.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 38.89 ps    (17.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 50 ps       (22.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 61.11 ps    (27.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 72.22 ps    (32.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 83.33 ps    (37.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 94.44 ps    (42.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 105.6 ps    (47.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 116.7 ps    (52.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 128.9 ps      (58 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 140 ps        (63 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 151.1 ps      (68 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 162.2 ps      (73 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 173.3 ps      (78 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 184.4 ps      (83 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 195.6 ps      (88 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 206.7 ps      (93 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 217.8 ps      (98 %), step = 1.111 ps     (500 m%)
Conv norm = 879, max dI(L3:1) = -78.9957 uA, took 30 ms.


==============================================
`sweeppss-000_pss': time = (0 s -> 222.222 ps)
==============================================
    sweeppss-000_pss: time = 5.556 ps     (2.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 16.67 ps     (7.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 27.78 ps    (12.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 38.89 ps    (17.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 50 ps       (22.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 61.11 ps    (27.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 72.22 ps    (32.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 83.33 ps    (37.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 94.44 ps    (42.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 105.6 ps    (47.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 116.7 ps    (52.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 128.9 ps      (58 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 140 ps        (63 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 151.1 ps      (68 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 162.2 ps      (73 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 173.3 ps      (78 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 184.4 ps      (83 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 195.6 ps      (88 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 206.7 ps      (93 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 217.8 ps      (98 %), step = 1.111 ps     (500 m%)
Conv norm = 3.13, max dV(nm2.main:gmnode) = 45.1096 uV, took 50 ms.


==============================================
`sweeppss-000_pss': time = (0 s -> 222.222 ps)
==============================================
    sweeppss-000_pss: time = 5.556 ps     (2.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 16.67 ps     (7.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 27.78 ps    (12.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 38.89 ps    (17.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 50 ps       (22.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 61.11 ps    (27.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 72.22 ps    (32.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 83.33 ps    (37.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 94.44 ps    (42.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 105.6 ps    (47.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 116.7 ps    (52.5 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 128.9 ps      (58 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 140 ps        (63 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 151.1 ps      (68 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 162.2 ps      (73 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 173.3 ps      (78 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 184.4 ps      (83 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 195.6 ps      (88 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 206.7 ps      (93 %), step = 1.111 ps     (500 m%)
    sweeppss-000_pss: time = 217.8 ps      (98 %), step = 1.111 ps     (500 m%)
Conv norm = 6.84e-03, max dI(L4:1) = 385.083 pA, took 30 ms.

pss: The steady-state solution was achieved in 4 iterations.
Number of accepted pss steps = 200.
Total time required for pss analysis `sweeppss-000_pss' was 160 ms.


++++++++++++++++++++++++++
sweeppss: prf = -36 (10 %)
++++++++++++++++++++++++++

Andrew Beckett over 9 years ago

Is there a good reason why you're using a spectre version from 11 years ago? That's a very long time ago in the high tech world and there have been 11 major releases of MMSIM since then. So maybe you're hitting a bug or a sensitivity to something that has changed in the models in the meantime, but the first thing I'd try is to run something newer.

Regards,

Andrew.
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encik RFIC over 9 years ago

you did mention about the size of circuit, how it is affect the PSS analysis ?
i attached the schematic here...maybe you can figure something out from that..still trying to simulate the linearity properties here...the reason why im using older version is that i am a student and only this version that my university provided...so we need to put out the choice of using newer version to simulate the 1 db compression point and the input IP3

your advice is very much appreciated sir...please help me
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encik RFIC over 9 years ago

Any advice Mr. Andrew ????
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Andrew Beckett over 9 years ago

I've been travelling. The advice is (and was) not to use an 11 year old version of spectre. The size of the circuit is unlikely to be a problem here since it is very small.

I can't really go back and check if there was a problem with swept PSS analysis in such an old version, but I find it hard to believe that if it was an issue, it would still remain this amount of time later given the enormous number of people who will have run PSS simulations in the meantime.

If your university only offers such an ancient version of the software to users, you should go and complain to somebody - there have been massive developments in the tools in the intervening years, and you're really missing out.

Regards,

Andrew.
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