There are two types of Mosfets:
Tipo nMOS: Substrato de tipo p e difusões de tipo n.
Tipo pMOS: Substrato de tipo n e difusões de tipo p.
I bought some cheap IRF640 from a locar distributor.
I can not identify the OEM
It reads IRF640 Y03K AB
Is it possible these are fakes ?
I can not identify the OEM
It reads IRF640 Y03K AB
Is it possible these are fakes ?
For the REFLEKTOR, could we made a MJE variant for 3.3v Vout as for the SSLV by simply replacing the mosfet shunt ?
Just finished the Reflektor and it fired ok. Looks promising. very stable on the bench with a 1kr load.
Very easy to set voltage out.
Strangely, I set it to 10.00Vout and it is loosing voltage with time... 10.00 ~9.99 ~9.98.... As it heats up.
I will let it running for a while now.
My choice of 3r3 // 10r for R1 was spot on.... It is running at 250mA.
Very easy to set voltage out.
Strangely, I set it to 10.00Vout and it is loosing voltage with time... 10.00 ~9.99 ~9.98.... As it heats up.
I will let it running for a while now.
My choice of 3r3 // 10r for R1 was spot on.... It is running at 250mA.
It seems the IRF640 are ok after all... I got them from a local distributor (Robert Mouser). This guy is German so I guess he only sells good stuff.
As it heats up some things change a little, like Vgs, Vbe(s), let it come up and then fix it with the trimmer.
Yes this is not a ideal case/choise for Zo, but do you think that the overall result is expected to be (even marginally) better than SSLV1.1-MJE version or perhaps worse ?
yes! use mje for 3.3 to 5v, it is better than IRF 9240 or 9540!
only get it when use measure!
thanks
Not as good as the swiss guys but one of the best.
I have been in Germany and know people like quality. I did not find one chinese store in Duisburg or Krefeld.
Trimming after it is hot provides very stable 10.00Vout.
What seems strange is that when powered from cold, it takes 10 seconds to reach 10.13Vout and then starts to go down. It takes 10 minutes to stabilize at 10.00Vout.
In all my other regs the voltage only goes up until it stabilizes.
I will now build a second shunt so I can test them in my p2p DCB1.
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As far as I can recall, all/most of my Salas type shunt regs dropped in voltage as they warmed up to final operating temperature.
I don't recall which transistors, but one or two had a +ve temp coef.
I never fully understood the temp coef mechanisms to make any sense of how to significantly improve temp stability. Keep it cool works !
Reading Roender's amp with it's various temp coef corrections was a revelation for me.
I don't recall which transistors, but one or two had a +ve temp coef.
I never fully understood the temp coef mechanisms to make any sense of how to significantly improve temp stability. Keep it cool works !
Reading Roender's amp with it's various temp coef corrections was a revelation for me.
guys what do you use for snubber?
i use 1n5822 diodes.
i have some on hand wima mks2 0.1uf/100v
are they any good?
i use 1n5822 diodes.
i have some on hand wima mks2 0.1uf/100v
are they any good?
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