I believe I can forget the transformer and BR1 rectifier. Do I still need C1?
C2, c3 and c4 are still good?
My main question is, what voltage do I need, and how to connected to the arduino. I have read the specs, but it's confusing to me...
I read about Vin, the power jack plug, and direct power and on-board regulated power???
What do I need to do? Create a 5v power supply and connect it with Vin? or do I need to create a 9v power supply to the powerjack or Vin?
I can create a 5 6 7.5 9 10 or 12v power supply, whats the best, and how to connect it?
Someone advised me to use a switching power supply, but they say they are complicated to build. I already bought a 3-Terminal 5V 1A Switching Voltage Regulator 5v 7805 3-pin compatible voltage regulator.
But now I'am not sure what voltage I need to generate for the Arduino, and what inputs I need to use.
If it's 5v, I will use this switching module. But if it needs to be 9v I think it's better to build a simple power supply with the 7805.
I know it's not efficient, but it's only used for powering the arduino, some 5mm leds, mosfet and a blue backlight 20x4 lcd.
The powerleds use 60 watts, so 2 watts waste on the 7805 does not hurt.
And if I use this ready switching voltage regulator, I'am not sure what components I use with this. It's going in it's place of the 7805. At product description they say "It is recommended to put minimum of 100uF capacitor across the output voltage to ground (ideally 330uF). "
Do I need to replace C4 with a 330 uF? And how much voltage does that need to be? How can I know? And C3 and C2 can be removed from this circuit than?
I first need to know what voltage I need to generate, and on what input.
But I heared voltage above 12v can make the arduino hot.
They advised between 7-12v. Than I could pick 9v.
But if I do not use any voltage regulation, can the arduino provide enough power. I need to use the Arduino, 4 5mm leds, 1 backlight 20x4 lcd and mosfets/transistors.
And the voltage regulator on the arduino is not a switching one?
I also have the LM317 maybe that could be an option if I would dicide to make 9v?
I checked, the lcd runs on 5v, and a max. 250mAh.
I think I do not need any regulators.
I gues it's also posible to paste a small heatsink on the arduino regulator, just some extra cooling.
Do I need to use the power plug, or can I use Vin, Vin would be easier with a pin...?
Do you know if the lm317 would be more efficient than a 78xx?
I may going to need 12v for three 50mm fans or is there an other way, maybe a resistor?
Can you advise me a page where I can learn more about components in cicuits, and where I can learn to build switching power supply's?
Maybe some day I'am going to need it anyway.
Richard, do you know of any of those chips that would make it dead simple to make a regulated 5V or 12V (etc) supply like the 78xx/79xx series?
I took a look at the datasheet for the MC34063A on Sparkfun's site, and while I must say that using that chip probably makes for a much simpler switched-mode supply than other methods, it certainly doesn't come anywhere near close to the simplicity of the 78xx/79xx regulators.
It seems, though, that most of the remaining complexity is deciding what kind of output you want, and then wiring up several external components (inductors, etc) to achieve that; its like the 555 for switched-mode supplies.
It it were possible to buy such a simple chip and only add one or two fairly common components, and get a fixed output of 5V or 12V (or whatever) like the 78xx/79xx series of regulators, that would be ideal.
Gravitech advertises this as a drop-in replacement for three-terminal regulators:
They don't provide much info on it, but it seems to be based on the LM2575.
Building a switching supply isn't that hard if you have a design to copy; the difficulty is mostly in finding the right inductor. Here is a 5V one from National: http://www.national.com/an/AN/AN-1120.pdf
The design circuit of the LM2675-5.0 does not look verry dificult, on the partlist I see "47 [ch956]H Power Inductor, Coilcraft D03316-473" I think I can buy that one...?
But it still is a 1A design. Can a 5A design be as simple as this one? http://www.national.com/an/AN/AN-1120.pdf
Does someone know if there are kit's for sale that hold all components in one package? And build it yourself?
I bought a DC-DC adjustable voltage regulator from ebay. It uses the LM317T. I do have 20 pcs of LM317 here, I think I can build more of them by looking at the complete design. But I think the 3 pins are different. The middle pin seems to be the output, the thirde pin the adjust, and the first pin the input. Is the "T" different from the standard?
I did buy the 3-pin compatible switching 5v 1A.
On the sticker on the chip I see "ET-LM2575-5 v2.0
I have not tested it yet. But it only uses one 330uF at the output I believe.
But making my own 11.5v 10A switching power supply is not going to happen, I going to use resistors that will desipate around 20% of the power used by the flashlight.
Do you know if I need a power supply for three 12v case fans? Or can I also use a resistor for that? (from 14.8v)?
Maybe it is also posible to use the recharge/voltage monitor plug on the lipo battery to create a 3 serie power output from 11.1v?
Or doesn't it work that way? 14,8v from the dean plugs, and 11.1v when connecting the cells with the recharge plug?
I try to explain.
A 3cell lipo has 11.1v, 4cell 14.8v.
A lipo has a dean plug, two wires that give the total voltage of all cels in series.
But a lipo battery also has a recharge plug. This is a five wire plug, with this plug the charger can charge cell independant.
The leds uses the 14.8v from the dean plug. But is it posible to use the recharge plug to also create a 11.1v power source at the same time the 14.8v dean is used?
That way I can use 3cell in series for the arduino and fans.
11.1v sould work I think, the fans need 12v, it's close enough.
What would happen if I create a series witch the recharge plug?
I understand I can't use resistors in order to let the fans work on there rated power?
The fans will blow everytime the leds are on, so I want to drive them correctly.
I think you never worked with lipo batteries...?
It doesn't matter whats being powered.
My question was if you can make smaller series of a 4 cell/4 series lipo battery using the recharge plug wish has separate cell wires.
But to be sure I'am going for a 12 78xx with 1A, more than enough to power the fans. The lipo can get out of balance when I'am not using all cells at the samee load. And it may get imposible to monitor voltage with the recharge plug because of the series I make with them.
If it's not posible to make 12v fans run on 14,8 with a resistor I will go for the 78xx 1A supply.
