FET and mosfet: reading numbers.

For the three and more legged things
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#1 FET and mosfet: reading numbers.

Post by Paul Barker »

Are they like valves where numbering from left to right underneath or is it from above?

Thanks.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Nick
Site Admin
Posts: 15694
Joined: Sun May 06, 2007 10:20 am
Location: West Yorkshire

#2 Re: FET and mosfet: reading numbers.

Post by Nick »

Best to find a data sheet

Though these two seem to contradict themself

Image
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#3 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

This is the problem it’s not clear in the data sheet drawings.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Mike H
Amstrad Tower of Power
Posts: 20156
Joined: Sat Oct 04, 2008 5:38 pm
Location: The Fens
Contact:

#4 Re: FET and mosfet: reading numbers.

Post by Mike H »

You're not alone I have same problem! Must never assume

I always go to datasheet sometimes draw the outline on the label on the packet
 
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
User avatar
Nick
Site Admin
Posts: 15694
Joined: Sun May 06, 2007 10:20 am
Location: West Yorkshire

#5 Re: FET and mosfet: reading numbers.

Post by Nick »

Just to be awkward most fets are symmetrical. What device are you using. The sheets them self are normally clear, the one I posted had had a extra drawing added to confuse matters,
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#6 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

2sk170 and 2sk246


Ive figured its as looked at in same way we look at valves to see pin numbers from underneath.

my devices not in manufacturer’s box so no data with them, and as youve both said : not conveyed communicatively by the manufacturer’s in their data sheets.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
IslandPink
Amstrad Tower of Power
Posts: 10041
Joined: Tue May 29, 2007 7:01 pm
Location: Denbigh, N.Wales

#7 Re: FET and mosfet: reading numbers.

Post by IslandPink »

Nick wrote: Tue May 12, 2020 8:52 pm
Though these two seem to contradict themself
Erm.. no they don't ?
The upper diagram in the first picture is looking from the 'back' - the flat bit.
"Once you find out ... the Circumstances ; then you can go out"
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#8 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

I’ve since discovered the protocol is TOP view. Opposite of valves.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Nick
Site Admin
Posts: 15694
Joined: Sun May 06, 2007 10:20 am
Location: West Yorkshire

#9 Re: FET and mosfet: reading numbers.

Post by Nick »

It should say, but here are two sheets from the same company for the same device that show different pinouts. (one from the bottom, one from the top)

http://www.linearsystems.com/lsdata/dat ... 8%2028.pdf
https://shop.micross.com/pdf/linear_lsk170.pdf
Erm.. no they don't ?
The upper diagram in the first picture is looking from the 'back' - the flat bit.
Yes, and the lower of the two top drawings is looking from the base of the device, otherwise the leadouts should be dashed. Depends on if its first or third angle I guess.

The upper diagram is looking at the device with the flat towards the viewer, so pin 1 is to the left, but the lower sketch has that pin as the Source, but the table says pin 1 is the Drain
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#10 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

Help!

Ive gone off transistors real quick, I’m probably going back to valves.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Nick
Site Admin
Posts: 15694
Joined: Sun May 06, 2007 10:20 am
Location: West Yorkshire

#11 Re: FET and mosfet: reading numbers.

Post by Nick »

The gate is the middle that will do in this case.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#12 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

Near as damit
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Paul Barker
Social Sevices have been notified
Posts: 8836
Joined: Mon May 21, 2007 9:42 pm

#13 Re: FET and mosfet: reading numbers.

Post by Paul Barker »

Flat facing away from us views from top it’s dgs left to right, right?
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
User avatar
Nick
Site Admin
Posts: 15694
Joined: Sun May 06, 2007 10:20 am
Location: West Yorkshire

#14 Re: FET and mosfet: reading numbers.

Post by Nick »

Other way around. The micros doc is from the bottom.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
User avatar
ed
retired
Posts: 5384
Joined: Thu Jun 21, 2007 4:01 pm
Location: yorkshire
Contact:

#15 Re: FET and mosfet: reading numbers.

Post by ed »

got the devil in me this morning.......

I remember back in the day scratching my head for a while...the Tosh data sheets(at least the ones I have) do not show the orientation(from top or bottom) and a lot of people made errors when building the first watts back in the day, precisely because of this. Perseverence, feint hearts and fair maidens win the day.....don't give up Paul, it really is worth it.

so I sympathise to a point.....BUT...
since linear started producing these the orientation is always shown....and so it is for the passed on micross sheets. As we are talking about the same parts, the Linear sheets explain the Toshiba sheets so today there should be no probs.

I can only guess at the time that Toshiba would have thought people using these devices would have come from the valve world and would therefore consider standard viewing to be from the bottom.

I'm sure there will be more confusing viewpoints to come...
There's nowhere you can be that isn't where you're meant to be
Post Reply