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sharpie7 / circuitjs1

Electronic Circuit Simulator in the Browser
GNU General Public License v2.0
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1N4148 diode voltage drop differs with other program #474

Closed Shichiya-San closed 4 years ago

Shichiya-San commented 4 years ago

I've constructed a simple circuit, but the voltage drop for the wire after the diode differs from other program such as LtSpice/ CircuitLab. Given that the max AC input voltage is 1.5V @ 1khz, resistor = 3.3k and diode is using 1N4148 model. V1 is obtained from the wire after the diode.

Circuit built using Circuitjs

https://imgur.com/a/UVfwewY The peak negative voltage shows -293.523mV

By using the same circuit on CircuitLab,

https://imgur.com/a/sgglWhN I get peak negative voltage of -524.3mV

Similar results of -524.3mV was obtained by using LtSpice. Is there a configuration problem with my circuit or some settings I haven't adjusted?

pfalstad commented 4 years ago

Oh no! That model is completely broken. Try this one: http://tinyurl.com/y6h3y9a2

Shichiya-San commented 4 years ago

547.536 might be a bit high, precisely the peak value from LtSpice are between -528~-529mV. I have no idea if the diode varies between application to application but 547.536 are still a bit off the 520~530 range. Is the value correct?

Sorry for the bad English and thank you for replying! Love your work

pfalstad commented 4 years ago

The datasheet shows a range of possible values. It seems that a variance of 20-30mV is within that range. I checked the model against the datasheet and it seemed to match.

You could use this model instead: http://tinyurl.com/yy6lwk2u I copied it directly from CircuitLab. I don't know if their model is better or not.

Shichiya-San commented 4 years ago

The datasheet shows a range of possible values. It seems that a variance of 20-30mV is within that range. I checked the model against the datasheet and it seemed to match.

You could use this model instead: http://tinyurl.com/yy6lwk2u I copied it directly from CircuitLab. I don't know if their model is better or not.

Ahhh then I see no problem, thanks for the hotfix! Will the fixed diode be updated for the offline version? I like to run this program but unfortunately I don't always have internet access.

pfalstad commented 4 years ago

Yes, eventually.