Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
In case anyone else is having the same problem like me, here is how I solved it:
The "logic" input comes from the Arduino (actually in my case from a shift register). T1 is the humble 2n2222, T2 is IRL3705N - or any other N-Channel power MOSFET with logic level gate, R1 is 10k, R2 - 100k. R3...
Out of curiosity just connected one LED to a 5V power supply, over a 2.2 Ohm resistor. Everything runs cold, current is ~0.22A and the voltage drop over the LED is ~4.5V. Could there be any problem with this approach? I have a bad feeling that there is a reason for all this complicated circuits...
Thanks to both of you @hyprfrcx and @betwixt for your answers. I suppose my question was not well formulated. I'll try to be more precise:
I have 9 LED's, which consume about ~260mA current each. The Arduino switches them on and off over 2n2222 transistors with 200 Ohm resistors between the...
Hi,
I have a couple of power-LED's, which I intent to control with an Arduino (not directly, with transistors), to achieve chase lights or other patterns. After trying different resistors, I gave up because of the heat problems. I found following circuit in an ON Semiconductor application...
Thanks all for the replies!
@barry - you are of course right about my description :) The current experiment I am working on is about watching 6x24V inputs. Anyway I though that in general would be easier to add some more small components than another Arduino if one needs to watch more inputs...
Hi,
like the title says, my aim is to detect on/off states on a 24V input with a microcontroller (arduino). A pretty common problem, for the looks of it, but none of the found solutions meets all of the following criteria:
- the input may vary to some degree (22-30V);
- ideally no heat...
Yes, this is exactly what confuses me - after narrowing as much as possible I am getting as much as some hundreds results (most extreme is with mouser), still somehow expecting to get one candidate which is "the single best one". I suppose I have to get used to this and follow your approach when...
Thanks @KlausST, @E-design and @frankrose for submitting so much info and circuits on my thread! Can't wait to build and test them all.
Now I build the circuit from KlausST, but with a PNP (2N3906) and no zeners because these are the parts I have available right now. The circuit gets driven...
@E-design :
One more thing - as I am reading about ground connected load, it is almost always that the supply voltage has to be precise and stable. This is not the case here, because of the zener, right?
Thanks!
A couple of questions:
- The 5V reference means something like this one ?
- Does R1 control the current upper limit? I am trying to understand the circuit in general.
As a side one - what is the simulation software you are using - it looks interesting
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
