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vt and vh from Texas Instruments PSpice model - not recognised

Hi

 

My name is Jesper, I'm a Mechatronics student at the University of Southern Denmark with focus on power electronics. This is my first post on this forum.

 

I have a problem with an inported PSpice model from Texas Instruments (Attached).

I have followed the import tutorial (http://www.ni.com/tutorial/3173/en/), but get the following errors when simulating:

 

 

 

------ Checking SPICE netlist for Design1 - 8. november 2016, 11:35:44 ------
SPICE Netlist Warning in schematic RefDes 'u1', element 'sosc':  Unknown model parameter 'vt', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes 'u1', element 'sosc':  Unknown model parameter 'vh', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes 'u1', element 'suvlo':  Unknown model parameter 'vt', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes 'u1', element 'suvlo':  Unknown model parameter 'vh', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes '', element 'sosc':  Unknown model parameter 'vt', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes '', element 'sosc':  Unknown model parameter 'vh', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes '', element 'suvlo':  Unknown model parameter 'vt', this parameter will be ignored.
SPICE Netlist Warning in schematic RefDes '', element 'suvlo':  Unknown model parameter 'vh', this parameter will be ignored.
======= SPICE Netlist check completed, 0 error(s), 8 warning(s) =======

 

 

The problem seems to stem from vt and vh not being recognised in Multisim.
Can anyone elaborate on how to solve the issue or move closer to a solution?

 

****OSCILLATOR*****
STOF1 8 GND RTCT GND SOSC
GBDISCH RTCT GND Value = { IF ( V(8,GND) < 2.5 & V(13,GND) > 2.5, 8.4M, 0 ) }
RPULL 8 VREF 100K
****UVLO***********
STOF2 VDD 19 VDD GND SUVLO
RUVLO 19 GND 1MEG

 

**********************

.MODEL SOSC VSWITCH (RON=.01 ROFF=1MEG VT=1.45 VH=0.95) ; VT=1.45 set to match 53k @ 3.3n/10k
.MODEL SUVLO VSWITCH (RON=.01 ROFF=5MEG VT=8.0 VH=0.4)

 

 Any help will be much appreciated.

BR Jesper

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I found the solution to the problem!

 

Looking up the VSWITCH command I found VSWITCH(RON=X ROFF=X VON=X VOFF=X)

Changeing VT to VON and VH to VOFF solved my problems.

 

Unfortunately something is still wrong in the model regarding the Oscillator

****OSCILLATOR*****
STOF1 8 GND RTCT GND SOSC
GBDISCH RTCT GND Value = { IF ( V(8,GND) < 2.5 & V(13,GND) > 2.5, 8.4M, 0 ) }
RPULL 8 VREF 100K

*********

.MODEL SOSC VSWITCH (RON=.01 ROFF=1MEG VON=1.45 VOFF=0.95) ; VON=1.45 set to match 53k @ 3.3n/10k

 

Having a capacitor placed between RTCT and ground and chargeing it through a large resistor results in a large enough voltage (above 1.45V) but does not seem to trick the switch. Any suggestions?

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