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Simulators >> Circuit Simulators >> Spectre simulation using SPICE model
https://designers-guide.org/forum/YaBB.pl?num=1549984907

Message started by hzhang on Feb 12^th, 2019, 7:21am

Title: Spectre simulation using SPICE model
Post by hzhang on Feb 12^th, 2019, 7:21am

Hi,

I tried to use spectre simulator to simulate a SPICE model of a power MOSFET and the SPICE model was imported following the instructions from https://community.cadence.com/cadence_blogs_8/b/rf/posts/tip-of-the-week-how-to-simulate-a-subcircuit-netlist-with-spectre-in-ade. The SPICE model can be found in https://www.onsemi.com/PowerSolutions/supportDoc.do?type=models&rpn=NJT4031NT1G and its name is NTP75N03.sp3.

I could get the simulation to run but the result seemed not correct. The simulation was to get IV characteristic, i.e. Id vs Vgs and the schematic is shown in the attachment[img][/img]. The gate voltage is dc swept from 0V to 10V and drain voltage is constant 10V. According to the datasheet, threshold voltage is about 2V, but the simulated drain current was constant 0A.

Please take a look and I really appreciate if you could give some suggestions. Thanks.

Title: Re: Spectre simulation using SPICE model
Post by Andrew Beckett on Feb 12^th, 2019, 7:41am

I ran (from command line, because I was lazy and didn't want to set up the symbol) with this netlist:

Code:

//

include "NTP75N03-06.SP3"

parameters vi=10 vg=2
M1 (d g 0) ntp75n03\-06
Vd (d 0) vsource dc=vi
Vg (g 0) vsource dc=vg

sweepvd sweep param=vi start=1 stop=10 step=0.5 {
dc dc param=vg start=0 stop=10 step=0.1
}
save M1:1

Here's the curves I got - I've selected the vi=10 curve (I simulated without sweeping the drain voltage initially). Is that not what you got? Doesn't look to unreasonable to me, but I didn't check the datasheet.

Title: Re: Spectre simulation using SPICE model
Post by Geoffrey_Coram on Feb 12^th, 2019, 7:50am

The original post said the subckt was in NTP75N03.sp3, but I couldn't find that file; I found the same one Andrew did (NTP75N03-06.SP3) and various others that were even more different.

Title: Re: Spectre simulation using SPICE model
Post by hzhang on Feb 12^th, 2019, 7:59am

Hi, Andrew,

Thank you for your help.

Yes, the simulation result you got also makes sense to me. It seems that something went wrong when I tried to import SPICE model.

One more question, is your simulator spectre? My netlist is attached.
[img][/img]

Andrew Beckett wrote on Feb 12^th, 2019, 7:41am:

I ran (from command line, because I was lazy and didn't want to set up the symbol) with this netlist:

Code:

Title: Re: Spectre simulation using SPICE model
Post by hzhang on Feb 12^th, 2019, 8:01am

Hi Geoffery,

My bad. Yes, the used model name is NTP75N03-06.SP3.

Geoffrey_Coram wrote on Feb 12^th, 2019, 7:50am:

The original post said the subckt was in NTP75N03.sp3, but I couldn't find that file; I found the same one Andrew did (NTP75N03-06.SP3) and various others that were even more different.

Title: Re: Spectre simulation using SPICE model
Post by hzhang on Feb 12^th, 2019, 10:13am

Hi,

Problem solved and it was caused by my definition of terminal names.

Thanks for your help.

Title: Re: Spectre simulation using SPICE model
Post by Andrew Beckett on Feb 14^th, 2019, 12:42pm

Glad it was resolved. BTW, yes I was using spectre.

Regards,

Andrew.