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This is a question about the of electronic and .

I'm finally starting to learn how discrete devices actually work from the entertaining yet incredibly insightful and informative ElectroBOOM videos. In This CHIP Changed the WORLD! MOSFET (ElectroBOOM101 - 012)

We have N-channel and P-channel MOSFETs, with very old, basic symbols like these, with arrows on the source differentiating the types.

(I'm) not sure what the arrows are showing because when the transistors are on, the current can flow in either direction.

Anyway, the new updated symbols are - a bit more confusing, but at least they show the substrate tied to the source terminal, so you know what you're dealing with. (I'm) not sure what the arrow symbolizes. Anyway...

screenshots from "This CHIP Changed the WORLD! MOSFET (ElectroBOOM101 - 012)" https://youtu.be/lyfx8CL7AkI

Later, at about 09:18 in the video, discussing the significance of the body diode, the most complete and complex diagrams for MOSFETs are shown:

Thinking about it, maybe that's what the arrow in the MOSFET symbol is trying to show.

screenshots from "This CHIP Changed the WORLD! MOSFET (ElectroBOOM101 - 012)" https://youtu.be/lyfx8CL7AkI

Question: I'd like to know the history of these three sets of symbols - who (what person, or if necessary at least what organization) created the early set, and likewise for the revised set, and if possible the corresponding years.

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    \$\begingroup\$ They were all four-terminal devices diagrammed like this when I first encountered them in 1972-1973. This was how I was taught to draft them as a schematic draftsman at Tektronix. No power devices then and no 3-terminal devices, either. Not that I encountered, anyway. I still have a box of the old devices with four terminals each. I was pretty angry when they shifted over to 3-terminal devices. I kind of felt "cheated," since something was being stolen from me. But this was also about the time when power devices also became available some years later. \$\endgroup\$ Commented yesterday
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    \$\begingroup\$ MOSFET symbol - what is the correct symbol \$\endgroup\$ Commented 23 hours ago
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    \$\begingroup\$ Those noodling transistor heavy design ideas by hand, and especially CMOS chip designers / teachers / students, would quickly find the "full" symbol tedious. I can see why the JFET-like symbol shown at the top is so appealing. Add in the possibility of connecting the body terminal in different ways inside a chip, and at least in that context I can see why they chose to go that way. Maybe others eventually started to copy what they saw the CMOS folks do? \$\endgroup\$ Commented 18 hours ago

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I think the presenter is wrong here; I don't think any of the symbols shown are significantly more recent than any of the others. In fact, if I had to guess, I'd say the more simplistic symbols drawn on top are a more recent shorthand inspired by BJT symbols. There is also another set of symbols used in digital logic contexts that dispenses with the arrow and doesn't indicate the source at all, just using an inverter circle on the gate to denote a PMOS.

In the strict sense, the symbols the presenter shows on the bottom are not symbols for the common enhancement-mode MOSFET, either; as they are drawn with unbroken lines, they represent depletion-mode MOSFETs. An enhancement-mode MOSFET has the line representing the channel broken into three distinct regions that represent the drain, source, and substrate/bulk/body.

See this excerpt from IEEE 315-1975:
enter image description here

These are the most "official" symbols you'll find, replicated in other national and international standards. (The currently-active standard is IEC 60617, but I don't have access to that.) In IEEE 315, they're built out of standard building blocks representing the internal parts of the FET, so the ones in the excerpt are just presented as examples. In these, the source is denoted by having the gate terminal located on the side closer to the source, as the substrate is not necessarily tied to source (even though it nearly always is in discrete examples today).

To my knowledge, no symbols equivalent to the video's upper symbols are present in the standard, and the 1975 version is the first version of it. MOSFETs were rare in the 1970s, and no working ones had been made prior to around 1960, but the theory behind their operation had been worked out in the 1920s, so it's entirely possible symbols did exist and may have been different from those in IEEE 315, but I'm not aware of any standard symbols for MOSFETs that predate the ones shown in IEEE 315.

The third symbols (which I would not consider distinct from the second set), which were added to the question while I was typing this answer, merely show the intrinsic body diode. The arrow on the symbol sort of shows this, but in fact the arrow is the standard symbol for a PN junction; reading IEEE 315 can be educational if you're curious about how the symbols are constructed.

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    \$\begingroup\$ I was worried about the "1975" in the IEEE 315 standard until I saw that it was an active standard until very recently (2019) \$\endgroup\$ Commented yesterday
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    \$\begingroup\$ @uhoh I went with the 1975 version specifically to show that the symbols the presenter seems to say are "new" are in fact at least 50 years old, and may in fact predate the widespread adoption of MOSFET-based ICs. \$\endgroup\$ Commented yesterday
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the new updated symbols are - a bit more confusing, but at least they show the substrate tied to the source terminal, so you know what you're dealing with. (I'm) not sure what the arrow symbolizes.

The arrow shows the polarity of the substrate diode, and thus whether it's an N-MOSFET (arrow pointing in) or P-MOSFET (arrow pointing out).

Note that there are some MOSFETs that have the substrate coming out to a separate terminal so you can bias the substrate to an external voltage for certain special applications.
This is done in CMOS circuits where the substrates are connected to the plus voltage for the P-MOSFETs and the minus (common) for the N-MOSFETs.

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