Re: SMPS switching losses in LTspice?
The lack of such information suggests that the transistor might not be a good choice for this use. Jim Wagner Oregon Research Electronics
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Jim Wagner
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#72711
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Re: SMPS switching losses in LTspice?
potrstuvich, The data sheet specifies the gate drive voltage, Rg, Id and Vds. A MOSFET is almost always specified with an inductive load which means the load current is essentially constant during
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Rick
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#72710
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Re: SMPS switching losses in LTspice?
the mosfet I amusing in LTspice is http://www.mouser.com/ds/2/196/BSC159N10LSF%20Rev2.09-76560.pdf http://www.mouser.com/ds/2/196/BSC159N10LSF%20Rev2.09-76560.pdf BSC159N10. its datasheet gives no
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potstuvich
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#72709
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Re: Analog multiplier - wrong simulation or flaw in the circuit?
Hello Augustinto, There are two problems in your circuit. 1. The offset adjust circuit only works with a very few hundred milli Volts. See my test circuit. Analog multiplier 03_Vadjtest.asc
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Helmut Sennewald
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#72708
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Re: SMPS switching losses in LTspice?
You can get some idea of the accuracy by examining the Vgs during the switching interval. If Qg is similar to the datasheet, then Cdg is correctly included. Losses in capacitance will also reflect in
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boid_twitty
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#72707
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Analog multiplier - wrong simulation or flaw in the circuit?
I run across the schematic shown in page 13 of the RC4136's datasheet (uploaded). After 3 days trying to have it "working" in LTSpice (uploaded) I realized I need help. I tend to think I know the
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Agust¨ªn Tom¨¢s
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#72706
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Re: I can not find the file "Zip-files with all files from this group"
Hello Cristian, The zip-files are in the Yahoo group LTspiceFiles. See the link below. https://groups.yahoo.com/neo/groups/LTspiceFiles/files/LTspice%20Files/
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Helmut Sennewald
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#72705
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I can not find the file "Zip-files with all files from this group"
I can not download the file " Zip-files with all files from this group". Any help is welcome . Best regards Cristian
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C C
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#72704
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LM2917 F/V Tachometer simulation problem
A few days ago, 'hitec92407' uploaded the file "LM2917Test.zip" to the group's Temp area. Through my mistake, the discussion ended up on the [LTspiceFiles] group rather than this one. hitec92407's
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Andy I
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#72703
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Re: SMPS switching losses in LTspice?
potstuvich, I don't think it's a question of how accurate is LTspice, but instead, how good is the transistor model? If I really wanted to know the answer to this, I would build a switching time test
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Rick
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#72702
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Re: SMPS switching losses in LTspice?
I would expect it to be modestly accurate, then. Jim Wagner
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Jim Wagner
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#72701
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Re: SMPS switching losses in LTspice?
I am using the mosfet model of a mosfet provided by LTspice itself. So will the switching losses be accurate? The inductor in the real circuit will not saturate at the peak fet current level. Gate
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potstuvich
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#72700
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Re: SMPS switching losses in LTspice?
Should have written, instead of "losses will be mostly resistive" it ought to be "inductor losses will be mostly resistive" since gate charge losses CAN be significant. Jim Wagner Oregon Research
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Jim Wagner
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#72699
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Re: SMPS switching losses in LTspice?
Those voltage dependent FET capacitances are modeled well, if a good model is supplied, For an external FET switcher, that is up to you. The switching loss estimate is as good as your model. For
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Jim Wagner
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#72698
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SMPS switching losses in LTspice?
Hello, LTspice calculates a switching loss of 1.07W in the FET of the buckboost smps that I have uploaded to the Temp Files area. "Buckboost SMPS _switching loss.asc". How accurate is this to the real
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potstuvich
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#72697
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Re: Lock horizontal axis
Hell Stephen, I just tried with your mentioned setting and it works. Plot Settings -> Sync horizontal axis Best regards, Helmut
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Helmut Sennewald
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#72696
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Re: Pull-Push transformer for valve amp in LTspice
Tip: Ferrite cores are identified by an Al number, which allows quick determination of the number of turns, using the formula L=Al.N?
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Jerry Lee Marcel
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#72695
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Re: Pull-Push transformer for valve amp in LTspice
pha0001 asked: "why did you take a quarter of the total primary inductance? Why not just half it?" Adding to what Vlad already wrote (which should lead you to your answer), it does depend on the
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Andy I
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#72694
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Re: Pull-Push transformer for valve amp in LTspice
What's the equality between the ratios of the inductances and the number of turns? Vlad ______________________ ltspicegoodies.ltwiki.org -- holding, among others: a universal analog/digital filter,
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Vlad
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#72693
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Re: Pull-Push transformer for valve amp in LTspice
Thank you so much!!! Things are starting to become much clearer now. If you don't mind, may I ask, why did you take a quarter of the total primary inductance? Why not just half it?
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tom tim
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#72692
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