Danko,
You are partially correct. If R2 is connected as you suggested, it will pull up the base of Q1. However, when Q4 is on it's collector will be at about 12 volts. Thus, Q7 will most likely conduct. At best you will have some shoot through current. At worst, Q7 will fail.
Rick
You are partially correct. If R2 is connected as you suggested, it will pull up the base of Q1. However, when Q4 is on it's collector will be at about 12 volts. Thus, Q7 will most likely conduct. At best you will have some shoot through current. At worst, Q7 will fail.
Rick
fredos said:
Hi Fredos,
The Forward voltage Drop of both ES1D and the body diode of Mosfet/FredFet is almost same, then how could you use the fast recovery Characteristics of ES1D[With Iav=1 A] in conjuction with the body diode..doesnot it has little effect.......
Also the Magnitude of Freewheeling current in realworld conditions may exceed 1A rating of ES1D very easily, but then you aslo rely on the body diode or a Fredfet....
Kindly share some of your thoughs with us.....
regards,
K a n wa r
Attachments
It would have to be a fredfet I think, but if that's the case, why bother with the // diode at all.
Given the number of variables I'd think it would be best to suck up the extra diode drop and go with the workhorse version.
Given the number of variables I'd think it would be best to suck up the extra diode drop and go with the workhorse version.
Hi Chris,
I think its much better to stop the conduction of body slow diode of mosfet with series schottky's and use an anti-parallel high current fast recovery diode for dealing with Freewheeling current....in the output stage.........what do you think....
regards,
K a n wa r
I think its much better to stop the conduction of body slow diode of mosfet with series schottky's and use an anti-parallel high current fast recovery diode for dealing with Freewheeling current....in the output stage.........what do you think....
regards,
K a n wa r
the circuit in post #191, even it have been modified as danko said, how to charging the high fet's gate?
Totally agree that's what I was trying to get at. Their Vf vary with load, as will the turn off of the body diode, either by recombination alone or forced by output current, so many variables comming into play I find a // diode alone is useless.
So at the small hit in efficiency for the added anti series diode drop, it seems crazy not to use it, when it removes all those unknowns that you just can't rely on.
So at the small hit in efficiency for the added anti series diode drop, it seems crazy not to use it, when it removes all those unknowns that you just can't rely on.
The other problem is that imposible to pull the Q1 to totally zero at high speed. That is why I said the gate run slow and not easy to control cross conduction because of problem to switch off Q1 very fast.
I remember, it was sovadk's problem with that arrangement.
Still can not beat two pnp as UcD's.
Best regards,
kartino
I remember, it was sovadk's problem with that arrangement.
Still can not beat two pnp as UcD's.
Best regards,
kartino
kartino said:I am sorry, I mean that with no signal the high side will always on. I did not like that....
No one posted a working version or suggestion for it yet... why do they not simulate, especially before recommending it to someone?
Even I didn't simulate, I am sure for what I said.... No doubt that someone will lost of few dollars again...
kartino said:Even I didn't simulate, I am sure for what I said.... No doubt that someone will lost of few dollars again...
...and again..... and again..... aaaaand again. 😕
classd4sure said:I prefer the small signal one... but it's not what I'd use either.
If you had a better idea in level shifting why not share it with forum members here....
Because it's way too much of a "give me" type question, something I've spent alot of time researching, nothing nobody else can't find for themselves if they made half the effort, and everyone's little projects (..... or products) will end up the same.
classd4sure said:Because it's way too much of a "give me" type question, something I've spent alot of time researching, nothing nobody else can't find for themselves if they made half the effort, and everyone's little projects (..... or products) will end up the same.
😀 😀 😀 😀 😀 😉
Yes projects must be distinct from each other because we are not here for cloning each other's ideamatic genes.....🙂
🙂 Then again it's also application specific, so there's really no good answer anyway! I for one sure do not have stock of gate driver IC's....
Originally posted by classd4sure
Hi Tekko,
I built you circuit this afternoon, the mosfets melted into my breadboard and it caught fire. I don't know what's wrong with it, have more mosfets but no more breadboards. Now I see why you're using a PCB for prototyping. A jamaican told me it was because my air coils are EMI infernos. What core should I use?
Chris,
Which fire extinguisher did you used to keep the things away from the burning inferno!😀 😀 😀 😀 😉
Cheers,
K a n wa r
Hi Kanwar,
Did your amp with air core finished?
I know that you did not need fire extinguisher, but why still ask to Chris anyway?
Did your amp with air core finished?

I know that you did not need fire extinguisher, but why still ask to Chris anyway?

Hi Kartino,
Yes it was finished a month ago, I did replace the air core with Gapped EE cores.......
Regarding fire Extinguisher I want to know which is the best brand in extinguisher so that every body could use them in case of fire infernos originating from Bread-Butter-Boards......
regards,
K a n w a r
Yes it was finished a month ago, I did replace the air core with Gapped EE cores.......
Regarding fire Extinguisher I want to know which is the best brand in extinguisher so that every body could use them in case of fire infernos originating from Bread-Butter-Boards......
regards,
K a n w a r
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