I am not lucky soldering JFETs and MOSFETs, although I am careful with static electricity and such.
Now I can vaguely remember I read a long time ago FETs were sold with the three leads, gate, drain and source clamped together with a peace of metal to protect it. After soldering the metal was supposed to be removed.
Is that method still advisable?
Any other advise?
Thanks!
Now I can vaguely remember I read a long time ago FETs were sold with the three leads, gate, drain and source clamped together with a peace of metal to protect it. After soldering the metal was supposed to be removed.
Is that method still advisable?
Any other advise?
Thanks!
First I was thinking pulling the mains voltage plug of the soldering iron and only then soldering the FET. But grounding it is a better idea, I will do that, thanks.
You may also want to check your clothing for anything which can generate alot of static charge. Synthetic fibers will build up lots of surface charge as well as rubber sole shoes ie training shoes. I also run a humidifier when its very dry which helps alot. Ground straps help, but aren't fool proof. They must be grounded at the same place as your soldering iron and work station mat.
That is also a good advice 👍 Once the FET is in place it is not as vulnerable anymore, right?
Yes, as long as the gate is terminated somewhere with other component connections on the PCB. The FETs should be installed last if possible.
Nice quality leaded solder is a must, lead free is horrific stuff. Recommend Cardas quad Eutectic for this hobby.
Metcal MX500 all day people, they have graded tips for specific temps.
Desoldering can cause more damage.
Metcal MX500 all day people, they have graded tips for specific temps.
Desoldering can cause more damage.
If you just have an iron that plugs into the wall, you should get a regulated station. An example:
https://www.ifixit.com/products/soldering-station-hakko-fx888d-23by
Your work surface should also have a static mat.
That looks like a nice soldering station, will consider it, thanks. But knowing myself i will try to use my trusted soldering iron anyway and shall see if I come away with that using all the tricks mentioned before.
Instead of the static mat I will be using the steel surface of the kitchen sink, will ground it before use.
Wear an ESD wrist strap and build on an anti-static mat. I use lots of mosfets and Jfets in my designs and have not had any problems with failures over my professional or hobbyist life. (4+ decades) Do check to make sure that the tip is grounded and the temperature is not excessive. (I typically use 700°F setting)
I assume that these parts are properly stored in ESD safe packaging, if the parts and assembly you are working on are charged up prior to soldering, the part will fail when you solder with a GNDed iron. You must make sure they are free of charge.
Consider a small humidifier during the winter months in the work space where you are assembling projects. Anything you can do to reduce ESD build up on you could help. (clothing, footwear) Carpets increase the risk of becoming a human discharge machine. 😀
I assume that these parts are properly stored in ESD safe packaging, if the parts and assembly you are working on are charged up prior to soldering, the part will fail when you solder with a GNDed iron. You must make sure they are free of charge.
Consider a small humidifier during the winter months in the work space where you are assembling projects. Anything you can do to reduce ESD build up on you could help. (clothing, footwear) Carpets increase the risk of becoming a human discharge machine. 😀
I will use all measures I read including yours (thanks!), I keep the JFETS in a metal box.
The suggestion about the parts charged before soldering and failing if the iron is grounded may be one of the reasons my attempts always fail. I tested the FETS to match them. Is that what you meant? Perhaps it is not a bad idea to clamp the three leads before soldering...
About the carpet, yes, unfortunately I have that...
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Metal box = muy bad IMHO, please keep in an ESD safe container within their original ESD safe packages. You should not need to short the leads together, that was a requirement for some very delicate dual gate VHF mosfets typically used in mixers and RF amplifiers back in the 1980s.
I use both through hole and SMD fets and mosfets and haven't had a problem here. In winter my lab/listening space often has an RH <= 20% and even then I have not lost any to date.
Barefoot on carpet is recommended, socks with a similar composition to your carpeting might help, but grounded mat and strap will definitely improve matters.
Good luck! 😀
I use both through hole and SMD fets and mosfets and haven't had a problem here. In winter my lab/listening space often has an RH <= 20% and even then I have not lost any to date.
Barefoot on carpet is recommended, socks with a similar composition to your carpeting might help, but grounded mat and strap will definitely improve matters.
Good luck! 😀
I've used crocodile clips to protect heat-sensitive components before, but... Blu Tack?
