NE555: LTSPICE model for NE555 IC

Hello Ron, I'm using the TLC555 Timer in my LTSPICE simulation. At first I was receiving an error stating "Can't resolve .PARAM NZ = {0.3/(VT*LOG(1 + 5.0M/ISZ))}". I researched this error online and found that the thermal voltage "VT" did not have a .PARAM statement defined. So I added a statement: ".PARAM VT=.026". I ran the simulation a second time. It finished and plotted the desired waveforms yet unfortunately in the SPICE ERROR LOG file I received the following errors shown below from the SPICE ERROR LOG. Unfortunately I fear that I won't be able to rely on these results due to the SPICE simulator ignoring several MOSFET parameters. Is there a workaround for this to get accurate results?

Error on line 11475 : .model tlc55x_pmosd_hv pmos level=3 l=10u w=100u kp= 3e-005  vto= -0.85  lambda=2e-3 theta=2.2e-01  cj= 0.00024  cjsw= 1.76e-009  cgso= 3.3150180477024e-011  cgdo= 3.3150180477024e-011  rsh=10 pb=0.65 ld=70n tox= 1e-007
    * Unrecognized parameter "lambda" -- ignored
Error on line 11462 : .model tlc55x_nmosd_hv nmos level=3 l=10u w=100u kp= 6e-005  vto= 0.8  lambda=2e-3 theta=1.8e-01  cj= 0.000144  cjsw= 8e-010  cgso= 3.3150180477024e-011  cgdo= 3.3150180477024e-011  rsh= 10 pb=0.65 ld= 70n tox= 1e-007
    * Unrecognized parameter "lambda" -- ignored

Instance "m:u9:mn10:1": Length shorter than recommended for a level 1 MOSFET.

Direct Newton iteration failed to find .op point.  (Use ".option noopiter" to skip.)
Starting Gmin stepping
Gmin = 10
vernier = 0.5
Gmin = 2.07126
vernier = 0.25
vernier = 0.125
vernier = 0.0625
vernier = 0.03125
Gmin = 1.99293
vernier = 0.015625
vernier = 0.0078125
vernier = 0.00390625
vernier = 0.00195313
vernier = 0.000976563
Gmin = 2.00068
vernier = 0.000488281
Gmin = 0
Gmin stepping failed

Starting source stepping with srcstepmethod=0
Source Step = 3.0303%
Source Step = 33.3333%
Source Step = 51.5152%
Source Step = 59.0909%
Source Step = 66.6667%
Source Step = 74.2424%
Source Step = 81.8182%
vernier = 0.375
Source Step = 90.5303%
Source stepping succeeded in finding the operating point.


max_output_voltage: MAX(v(v_meas1))=4.02539 FROM 0 TO 20
max_output_voltage2: MAX(v(v_meas2))=3.41004 FROM 0 TO 20

Measurement "max_output_voltage3" FAIL'ed

Measurement "max_output_voltage4" FAIL'ed

Measurement "voltage_change" FAIL'ed

Measurement "max_power" FAIL'ed

Measurement "max_comp_current" FAIL'ed

Measurement "min_comp_current" FAIL'ed


Date: Tue Apr 14 10:14:55 2020
Total elapsed time: 1.949 seconds.

tnom = 27
temp = 27
method = modified trap
totiter = 24167
traniter = 21459
tranpoints = 8182
accept = 5943
rejected = 2239
matrix size = 205
fillins = 201
solver = Normal
Thread vector: 54.0/28.3[6] 18.1/7.9[6] 7.4/5.4[6] 0.8/10.9[1]  2592/500
Matrix Compiler1:     954 opcodes  8.5/[4.0]/4.3
Matrix Compiler2:    1490 opcodes

Thank you,

Johnathan Williams

Hi Johnathan, 

Sorry to hear that you're having issues. We're not too familiar with LTSPICE simulator. 

Can you try this on TINA-TI and let us know if you're having any issues? You can download the software for free from: http://www.ti.com/tool/TINA-TI

Regards,

Bala Ravi

Hi Johnathan, 

I hope your issue is resolved. If not, please follow-up here. I will go ahead and close this thread for now. 

Regards,

Bala Ravi