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Topic: Basic Transistor with Arduino. Is this accurate? (Read 11964 times) previous topic - next topic

Bittsen


Whatever you do, DO NOT buy any Darlingtons


Thanks.
I'm abandoning the Darlington idea as simple as it would be, the benefits don't outweigh the sacrifices.

I found a pretty informative page here
http://arduinodiy.wordpress.com/2012/05/02/using-mosfets-with-ttl-levels/
that lists a few logic level Mosfets

It would be nice if there was a list of Logic Level Mosfets with noob descriptions. All the technical lingo makes me cross-eyed.

runaway_pancake

Noob descriptions... ohhhh

Here's my rec -- STP40NF10L
Others will have theirs (stand by).

"Who is like unto the beast? who is able to make war with him?"
When all else fails, check your wiring!

Bittsen


Noob descriptions... ohhhh

Here's my rec -- STP40NF10L
Others will have theirs (stand by).




Ha,
I have been playing with a p40NF0 all morning. By playing with it I mean I've been picking it up and trying to figure out if it would be right.
I think I have a few of these laying around.

I'm pretty sure I've figured out that the first couple (or few) letters are manufacturer numbers. My particular one is simply p40nf0 but has other numbers as well. Most important is that it has a ST logo.

larryd

#18
Mar 09, 2014, 09:24 pm Last Edit: Mar 09, 2014, 09:35 pm by LarryD Reason: 1
Quote
It would be nice if there was a list of Logic Level Mosfets with noob descriptions.

Why stop there?
Have  a list of  sketches and routines so all you have to do is cut and paste and not have too learn programming. ;)
No technical PMs.
If you are asked a question, please respond with an answer.
If you are asked for more information, please supply it.
If you need clarification, ask for help.

Bittsen


Quote
It would be nice if there was a list of Logic Level Mosfets with noob descriptions.

Why stop there?
Have not a list of  sketches and routines so all you have to do is cut and paste and not have too learn programming.


If we are going to use hyperbole, why not have to learn the programming so you can put gas in your car.
Or go to college to learn electrical theory to change a light bulb.

I don't know why people, like you, feel it's necessary for a hobbyist to learn engineering to be able to build a simple circuit.

larryd

If you don't learn the reasons why and why not, you get: why is this getting hot, why is this not turning on, it worked for a moment etc.
I recommend asking questions here  and you will get the help you need. There are some basic characteristics we recommend you to look at when selecting components.
There use to be a link "ABC Arduino" or something like that where you could down load a PDF of typical circuits for the Arduino. I recommend hunting it down if it is still available.
No technical PMs.
If you are asked a question, please respond with an answer.
If you are asked for more information, please supply it.
If you need clarification, ask for help.

Bittsen

See? That's where I like to live. Halfway between knowing everything and knowing nothing.
If there was a noob list of components, with their engineering add-on descriptions, then it would be much more useful to hobbyists than someone saying "use this one" without the "and here's why" added.

I am capable of looking up a component if I know it's basic function. I found a list of NTE logic level transistors and understood enough of what they were saying but I don't like NTE. I don't know why but I don't.

Graphs don't seem to help. Stating the maximum watts of wasted energy does.

If I found one with a max throughput of 17A @ 100V with a 60W max wasted energy, would that be a good one? I don't plan on 100V and I don't plan on 17A. So, in my thought process if I'm only using 10% of the maximum capability of the transistor then I should be around 6W of loss? I could live with that.

Bittsen

OK, this is where I'm at in my thought process.

Will this work?

Where would the flyback diode go?


runaway_pancake

Let's see what you've got.
Attached is a diagram for connecting that dude up.
The "load" could be a motor or LED/s + resistor.
+V could be +5 or "Vin".  You work that out.
"Who is like unto the beast? who is able to make war with him?"
When all else fails, check your wiring!

Caltoa

#24
Mar 09, 2014, 11:53 pm Last Edit: Mar 09, 2014, 11:55 pm by Caltoa Reason: 1
Bittsen, if you use a mosfet, please make a new picture with 'G', 'S', 'D'.
A n-channel mosfet is a low-side switch. It has the 'S' (source) connected to ground.

larryd

#25
Mar 09, 2014, 11:58 pm Last Edit: Mar 10, 2014, 12:12 am by LarryD Reason: 1
You are using a BJT image instead of N channel MOS fet IRL540.
If you are driving a incandescent lamp you do not need a fly back diode.
Use fly back diodes on DC components with a coil.
see this is what I mean.

Edit, see:
http://www.dnatechindia.com/Tutorial/Transistors/MOSFET-as-a-Switch.html
No technical PMs.
If you are asked a question, please respond with an answer.
If you are asked for more information, please supply it.
If you need clarification, ask for help.

Bittsen

I will reply in a bit. There's a three year old that's begging for my attention.

Bittsen

OK, new labels (I hope this is correct now).

I won't be using this, right away, for anything with a DC coil but I want to build a "go-to" thing for my future projects and I may, in the future, need a flyback diode.


runaway_pancake

Yes, but...

Yes, but that's missing the low-value resistor like I showed in my example.
It's a real good idea.

Did you try it?
"Who is like unto the beast? who is able to make war with him?"
When all else fails, check your wiring!

runaway_pancake

Crap!
Strike that.
You have +V and Gnd to the transistor wrong.

Why do I bother?
"Who is like unto the beast? who is able to make war with him?"
When all else fails, check your wiring!

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