Need NGspice Model for 74HC04 Inverter

Schematic Simulation (Ngspice)
1

Where can I find a good model for the 74HC04 inverter?

After searching for 30+ minutes I found this Spice Model site…
http://www.bordodynov.ltwiki.org/
with the file lib.zip unzipped It has a file 74HC.lib with a number of 74HC parts…
including the 74HC04 inverter… with the Model shown below…

* Inverter gate
* tpd 25n/9n/7n
* tr 19n/7n/6n
.SUBCKT 74HC04  A Y  VCC VGND  vcc1={vcc} speed1={speed} tripdt1={tripdt}
.param td1=1e-9*(9-3-3)*4.0/({vcc1}-0.5)*{speed1}
*
XIN  A Ai  VCC VGND  74HC_IN_1  vcc2={vcc1}  speed2={speed1}  tripdt2={tripdt1} 
*
A1  Ai 0 0 0 0  Yi 0 0  BUF  tripdt={tripdt1}  td={td1}  
*
XOUT  Yi Y  VCC VGND  74HC_OUT_1X  vcc2={vcc1} speed2={speed1}  tripdt2={tripdt1}
.ends
*

I saved this model as 74hc04.mod in my project folder and assigned it to the device as a subckt.

But I get an error when running the simulation…
Compatibility modes selected: lt
Circuit: KiCad schematic
Too few parameters for subcircuit type “74hc04” (instance: xxu?)
Background thread stopped with timeout = 0
Error: circuit not parsed.

Thanks for any help on finding the correct model and getting it to work.

2

The model is for one inverter. Your IC contains six of it. You have to write a model for the IC with six instances of the model coming from Bordodynovs library. His library is focussed on LTSpice. LTSpice doesn’t simulate multi gate devices.

Use this as template:

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3

The LTSPICE model of the 7404 uses proprietary circuit building blocks (e.g.

A1  Ai 0 0 0 0  Yi 0 0  BUF  tripdt={tripdt1}  td={td1}

) which ngspice cannot use.

Some digital models for ngspice (including 7404) are available at a link given in KiCad Eeschema as GUI for ngspice, tutorial for setting up the simulation.

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