Using THS4522 in QSPICE

QSPICE
1

Hello,

I would like to ask for some help to use the TI’s THS4522 modell in QSPICE. I found that somebody had a problem with THS4551 model, but that solution did not help me. Could anyone give some suggestions?

The connection between the .subckt and the symbol is “handmade” so it might contain mistakes (I attached it).

Ignoring shorted behavorial source: "G2•XI0•XI30•XI0•X1"
Ignoring shorted capacitor: "C2•X1•XI18•XI0•X1"
Ignoring shorted capacitor: "C2•X1•XI47•XI0•X1"
Ignoring shorted resistor: "R0•XI13•XI0•X1"
F:\AKTUÁLIS\THS4522\proba1\TEST.qsch
Warning: Source VPROBE1B•XI0•X1 has no value, 0 assumed.
Warning: Source VPROBE2B•XI0•X1 has no value, 0 assumed.
Warning: Source VPROBE2A•XI0•X1 has no value, 0 assumed.
Warning: Source VPROBE1A•XI0•X1 has no value, 0 assumed.
Warning: Source VPROBE4•XI0•X1 has no value, 0 assumed.
Warning: Source VPROBE•XI32•XI0•X1 has no value, 0 assumed.
Starting Gmin stepping.
Warning: Gmin stepping failed.
Starting source stepping.
Warning: Singular matrix. Check nodes VIH•XI24•XI0•X1#BRANCH and VINP_INT•XI0•X1
Warning: Source stepping failed at 0.0414485(1.16415e-16)
Starting pseudo transient analysis.
Pseudo transient analysis failed at t=0
Warning: Using skipbp
Warning: Singular matrix. Check node VRECH•XI29•XI0•X1#BRANCH
Warning: Singular matrix. Check nodes V0•XI25•XI0•X1#BRANCH and VINM_INT•XI0•X1
Warning: Singular matrix. Check nodes V0•XI25•XI0•X1#BRANCH and VINM_INT•XI0•X1
Warning: Singular matrix. Check nodes V0•XI25•XI0•X1#BRANCH and VINM_INT•XI0•X1
Fatal error: Timestep too small(1.25e-19) at t=0
[THS4522_testing.zip.txt|attachment](upload://mXnJGc4ReL3SQ5vE0eaE5Pd5rEk.txt) (17.9 KB)

TEST.qsch (8.8 KB)
THS4522.LIB (28.8 KB)
THS4522.qsym (1.2 KB)

2

Use Qspice80.exe to help convergence.

image
image1226×416 51.2 KB

Test.THS4522.Transient.qsch (28.6 KB)
THS4522(embeddedSUBCKT).qsym (21.1 KB)

1 Like
3

It seems it works well even without the double math option, propably the “handmade” symbol was deffective, anyway you are amazing, thank you!

4

If you can run my schematic without .option fastmath=0, check Edit > Preferences to see if fast math is already disabled. If I force .option fastmath=1, the schematic I uploaded still returns a timestep is too small.

Your schematic can run with Qspice80.exe too.
Well, your symbol also built correctly. However, when you import the .subckt, you didn’t select Include Entire File option ( MOV subcircuit component check (PBKAC) - QSPICE - Qorvo Tech Forum), and all dependent subcircuit not included, that why you still need .lib to link the library file.