Has anyone built symbols for Exicon Lateral Mosfets?

Schematic
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There is nothing difficult in creating a footprint and a symbol in kicad, it does not take very much time.

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Looks like this may have been a symbolic defeat?

BTW after designing power for 45 years, I had been unaware of Exicon and their MOSFETs. I did check out 1 or 2 datasheets. SFAIK the symbol for a lateral or linear MOSFET does not change relative to the others we use for enhancement mode MOSFETs.

  1. I am not so favorably impressed by the completeness of their datasheets, butā€¦

  2. If the device freedom from forward bias secondary breakdown is as good as they imply, this is just the device you need for an electronic load working up to 200V. Infineon makes ā€œlinearā€ MOSFETs but that portfolio seems to stop at 100V or 150V. IXYS>Littelfuse does seem to go up even higher in voltage.

https://www.google.com/search?q=MOSFET+FBSOA&rlz=1C1RXMK_enUS1029US1029&oq=MOSFET+FBSOA&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIKCAEQABiABBiiBDIKCAIQABiABBiiBDIHCAMQABjvBdIBCTg5NTdqMGoxNagCCLACAfEF__cEufbsp_c&sourceid=chrome&ie=UTF-8

  1. I have not seen a symbol on the Exicon datasheets. But this snip is from a Littelfuse>Ixys device, showing a standard enhancement mode MOSFET symbol.

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image1114Ɨ438 62.5 KB

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I think the OP has returned to Visio. Oh wellā€¦

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I use and like Visio. I used it for mechanical drawings and also for schematic illustrations (when my real schematic tool was ExpressPCB. That makes schematics that are functionally adequate but not up to what you would publish in an app note.) But Visio makes only dumb drawings so is not EDA.

I think that the OP made an argument for giving up. Teach your kids!!

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Is somebody going back to Visio a revisio-nary? :thinking:

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Oooooooooooooh :upside_down_face:

Now you have me confusing video and visio. The next thing you know, I will be promoting ClapChimp, or whatever they call that video editor. Is it called ChapClimp or ChipClamp?

I think I will go park my square wheeled wagon on a hill AND use handbrake. Donā€™t worry if you do not understandā€¦this is an inside jokeā€¦

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I made a symbol . . . just for you . . .

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. . . use it with this KiCad supplied footprint . . .

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All will be good :slight_smile:

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The Exicon parts are the only lateral mosfets left in current production. Vertical mosfets donā€™t work well in linear applications these days.
I think the OP has seen Eagle with its combined symbol/footprint structure before.

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I use drawio instead but never used their library for electronics

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Thanks. I might find out in the months to come. I may want to have a 150V electronic load, although I need only 10W. Based on the datasheet, the Littelfuse ought to work and to me it is a little more of a known entity.

Thanks I will need to check out drawio. I guess I am a ā€œroll your ownā€ (or is it ā€œre-invent the wheelā€?) sort of engineer. I have one Visio file full of schematic symbols that I created. Creating my own symbols is not a problem in either Visio or KiCad.

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Awesome ! may I use it to ? :rofl:
:mouse:

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Donā€™t forget to make a better heatsink.

IXYS seems to be the benchmark in linear MOSFETs

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Thanks. This guyā€™s test is pretty extreme!

I have a home made ~55V e-load which I built about 30 years ago. The photo and the real thing are sort of rough. A true work of art, huh? :crazy_face: I brazed the square steel tube frame together with an oxy-propane torch.

It has 200 mA, 2A, and 20A ranges. Each range uses an MTP3055E MOSFET driving 2 or 4 (I think TIP41) bipolars in a FETlington arrangement. So the FET is only a modest (not intended for linear use) device but it is only driving the power BJT bases so the current is not very high.

The heatsinks are only a couple of 0.1 or 0.125 inch (??) thick aluminum plates (no real fins). The thermal insulators are polyimide with a waxy thermal compound coatingā€¦I forget the tradename but that tradename may be long gone. Anywayā€¦this is your Kapton speaking. :grinning:

UPDATE: I remembered the trade name of the insulators. They are Crayotherm. I really do not remember that they seem to be from a Czech company:

What does work REALLY WELL is to press the TO220 plastic bodies + rubber pad against the polyimide + heatsink (donā€™t use the TO-220 hole) with a square rod and machine screws.

In all that time with occasional use, nothing has ever broken and the fan (controlled by a thermistor) has never turned on.

Bobs Bench Electronic Load
Bobs Bench Electronic Load2931Ɨ2739 205 KB

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Looking at the photo of the load, Iā€™d guess, if it overheats, the plastic ties will melt, the metal heatsinks? the ties support will drop, and the power will disconnect? :thinking:

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In that event, I will use it in Australia so that it will be mounted upside down and gravity will hold it together.

I am not sure that I could ever fix this thing if it breaks. Obviously I did not have KiCad when I built it. It is completely hand wired and I am not sure if I have my schematic diagram anywhereā€¦ :frowning:

In the lower right corner of the photo you see part of my 60 year old Belden ā€œstrip-itā€ wire stripper which looks like an overgrown staple remover. It really is good but it can pinch your hand badly if you do not watch it. Those are absoletely obsolute.

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Iā€™d thought this design was Bobā€™s rather ingenious idea for a 20 amp circuit breaker rather than a problem. It would save wear and tear on the fan. :slightly_smiling_face:

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You may, this time only . . . and please, donā€™t wear it out. :wink:

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Thanks.

I am very new to KiCad and struggling on two fronts and with getting my head around HOW to create what was required with new items. Searching on how to create symbols (google) gave me a headache as it pointed me to using Python ā€¦ eeee another language to learn (only just mastering Java scripts into functions in Node-Red). I could not find how to create whatā€™s required (end-end) in the KiCad Help (help was not in the downloaded version and the online help didnā€™t seem to match the version of KiCad I have installed).

Looks like I will do this retrospectively after I have mocked up the initial board design for testing. I have laid out the board (although for audio) using RF layout symmetry using my old tool (Visio) and created the photomask. Will etch, drill and construct the prototype for testing next week. Once I am happy with the slew resp I will then look at noise, distortion and power (then test protection as these devices are a little intolerant of short circuits [bad load]) but they are nice and linear. Although they colour coded the fets in parameter groupings to enable paralleling them without needing source resistors I am still using them. (plan on reducing from .2 ohm in steps of testing).

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I am clueless WRT Python, but I create symbols easily and almost routinely. Maybe you encountered some AI hallucination? :grimacing:

I have no observation supporting the idea that the symbol for a lateral FET is any different from other MOSFETs. The Exicon DS which I looked at had no symbol on it.

But anywayā€¦the way to make a symbol is to copy and edit one from the standard symbol library. No need to create it from scratch. I have also never used a symbol wizard.

If you want to create a new symbol, understand that the new symbol needs to be in your own custom library. Start with something from the standard library or I will be happy to give you what I have. Give it a try. If you get stuck, this is the place to ask for help.

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There is a version dropdown at the top right at the documentation website, needed now that the current version has been switched to 9.0. Hereā€™s the section on creating symbols for 8.0:

But as said before, most people do not create symbols for simple devices, there is usually a generic symbol that will suit. Thereā€™s is certainly a P-MOSFET symbol you can use.