LTSpice Hex inverter propagation delay and transistion time ?

Thread Starter

DarthVolta

Joined Jan 27, 2015
149
I have a plasma globe that uses a 4069 hex inverter as an oscillator and/or for modulating the plasma ball to respond to sounds...like music.

I have the datasheet for the hef4069 used, and so I have the H-L/L-H Prop.delays, and the trans. times. In LTSPice I will just use the logic inverter. How do I use the real values for the spice model ? IDK the default times, they'd probably be just fine anyways, but I'd try to use the listed values.
 

crutschow

Joined Mar 14, 2008
23,542
IDK the default times, they'd probably be just fine anyways, but I'd try to use the listed values.
You can measure the values in LTspice and see if they are close enough to the data sheet values for your purposes.
Otherwise you'll have to look in the model file for the 4069 and see if you can determine where the delay and transition values are listed.
 

eetech00

Joined Jun 8, 2013
1,726
I have a plasma globe that uses a 4069 hex inverter as an oscillator and/or for modulating the plasma ball to respond to sounds...like music.

I have the datasheet for the hef4069 used, and so I have the H-L/L-H Prop.delays, and the trans. times. In LTSPice I will just use the logic inverter. How do I use the real values for the spice model ? IDK the default times, they'd probably be just fine anyways, but I'd try to use the listed values.
Hi

The propagation delays are typically sensitive to the supply voltage. This is evident on the datasheet.
Is the power supply for the oscillator circuit regulated? If so, what is the regulated supply voltage?

If we can assume the supply voltage is regulated, and therefore at a fixed value, then we could use the native digital inverter and set the parameters to the appropriate values shown by the datasheet. That is straight forward. But if you want the behavior to reflect the dynamics of a varied supply voltage, then that would be much more complex for the part to simulate.

eT
 

Thread Starter

DarthVolta

Joined Jan 27, 2015
149
Excellent thanks guys. This reminds me of trying to mod Skyrim and Fallout 4

I want to get the real plasma globe put back together and measure it's current draw. It's a cheap ebay model, I'm not sure how safe it is to leave plugged in most the time, but I'd like to.


@ eetech00, it came with a step-down transformer, that I lost, I think it was like 8Vac, so around 10V after the FWR

IDK might have a suitable step-down trans, IDK if it's a good idea to try a using a 12V SMPS brick or not
 
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Thread Starter

DarthVolta

Joined Jan 27, 2015
149
So I've installed some parts by putting a .sym file and .sub file in the right place. How do I use the CD4000.lib file ?? I put in in the lib directory, and I've read something about adding a ".inc ______.lib" command in the schematic, but then what?


Bordodynov I got your HEF4069 installed, and IDK if I'm using them right. I right click on the inverter, and I see Vdd and Vss listed, so I just clicked on that and deleted "VDD VSS" and put in "6.2 0" Is that the right way to set Vdd and Vss ?

They are not working for me
 

Bordodynov

Joined May 20, 2015
2,428
No, you have to write down VDD 0 in this place. And you must have a schematic node named VDD on the schematic. The name in the schematic may be different, for example VCC or VDD2. Writing a name in the element symbol, you connect power to the node mentioned in the schematic.HEF4093.png
 
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