Voltage regulator?

I need to know how to build a 12v-5v pulse regulator for my fuel level sending unit/gauge in my truck. I would like to know what parts to buy and the order of everything. Thank you in advance. Daniel

Topic by gungfudan 6 years ago  |  last reply 6 years ago


Regulator Help

I am currently building an LED panel, and need some help setting up the regulators. I am using LM1084-ADJ regulators. What I was wondering is if anyone can tell me how to regulate the current, as in the math I need to calculate what resistance value I have to put between the adjustable, and Vout pins. The guy I was using simply stopped replying.

Topic by MaXoR 9 years ago


Voltage regulator? Answered

Does a voltage regulator IC (e.g 7805, LM317 etc) still draw current when there is no load?

Question by .Unknown. 8 years ago  |  last reply 8 years ago


Voltage regulation

I have a solar charge controller (Velleman SOL4UCN2) that outputs 12v, 6v and 3v. But I need 9v and I'm not sure how to get that.

Topic by pless84 10 years ago  |  last reply 10 years ago


Voltage Regulator

EDIT: Anyone Interested please check below posts, this is one is obsoleteHello!I need a voltage smoother and regulator on my circuit(attached below)it is a modified shunt charge controller circuit.It converts the Tri phase alternating current to DC and feeds it into the circuit.The regulator will have to be attachable to the BATTERIES wire in the circuit.It should not consume more than 1v power on its own.My Vout to the battery currently is fluctuating.I will need the to be a stable 12v to charge the batteries. A potentiometer will have to adjust current.I will calibrate current according to my battery bank needs.Led 1 indicates 'charging' Led 2 indicates 'Dump'And Please forgive my circuit diagram design(it looks like crap)but works like gold.Also do NOT suggest huge changes to my controller for the regulator to work. Small suggestions to make it more effective,useful like change the zener diode power rating will be welcome.P.S- Its for my hydro project.Check it out at https://www.instructables.com/community/Help-Hydro-power/Kabir

Topic by mhkabir 9 years ago  |  last reply 9 years ago


Regulating a Spark

I need to build a unit capable of supplying a timed spark. At approx 1 sec intervals. The unit will need to be small/cheap to build and be able to supply current as to generate a timed spark across two electrodes via 240v power supply. The unit I am attempting to build is a flammable gas warning/ignition device. The purpose of it is to ignite the first immediate gas detected, as to avoid a larger detination later. The unit will be made of machined aluminum. It will consist of a vapour detector hooked to a fan unit, which inturn vents the gas to the ignition device. Thus igniting the gas. At the moment I am working on the ignition system, hence the question. Thanks for any help.

Topic by Lftndbt 10 years ago  |  last reply 10 years ago


Small Voltage Regulator

I am looking to buy or build a small voltage regulator that can fit in an O gauge electric train engine. It needs to have a 18-20 volt AC input and 10-12 Volt AC 1 amp output. I would like to buy one already built, buy a schematic or a schematic with the parts to build. Thank You

Topic by frankv6 3 years ago  |  last reply 3 years ago


Help with Voltage Regulator

Hi, I have put one of these together for an ATX power supply and have come across something that I might be getting wrong.... In mocking up the LM317 circuit in breadboard (standar one found everywhere on line and on the LM317 pages), I have got the thing metering -11v to +11v??? I am using one of the black ground wires of the PSU on the black side of the volt meter, but cant figure out why I am not just getting positive voltages??? Could the diode be faulty? Or is this in fact correct? Any help appreciated...

Topic by lone_viper 7 years ago  |  last reply 6 years ago


Voltage regulator for laptop

Hi there. I have a problem for which I'd like some opinions: I have a PB laptop which has fried its inverter for the LCD due to the input voltage towards the inverter being too high (19v while it should be 12v and can only endure upto 13v). Most PB models have this problem. I looked around and some people suggest making a voltage regulator with a 7812 and some capacitors that gets its power directly from the input of the power adapter on the laptop (19v, 6+ amps). But since I am not really that into electronics, I have no idea if this will work, especially towards the heat that comes with the 7812, will it be high? The inverter needs around 0.5 amps input current. Others suggest a setup with (zener) diodes, but I have no clue how to start on that. Anybody have a suggestion? Many thanks.

Topic by .conne. 11 years ago


-5v Voltage Regulator

I want to make a -5v Voltage Regulator... Does anyone know if I replace the 7805 regulator with a 7905 would that be enough, or would the capacitors have to be different values?5v Voltage Regulator Schematics

Topic by mrshow555 11 years ago  |  last reply 11 years ago


will this really regulate voltage?

Will this really regulate voltage?I would think that voltage could just flow arround the capshttp://electronics.howstuffworks.com/digital-electronics4.htm

Topic by kendallickes 10 years ago  |  last reply 10 years ago


Varialbe current regulator?

Have you ever seen a variable current regulator? i googled it but i keep getting standard voltage regulators Any help would be appreciated!

Topic by Sandisk1duo 10 years ago  |  last reply 10 years ago


DC motor regulation

I am planning to build a small gearbox that depends on a steady rpm from a 3V dc motor. I understand that the output rpms will change in correlation to the fluctuation of input power. My question is, if I used a regulator to regulate the input voltage from 5V to 3V, will that keep the motor rpms steady?

Topic by Tman179 1 year ago  |  last reply 1 year ago


simple 5v regulator?

Today i made a shaking generator for a shaking flashlight.i am using a 5.5v 1F capacitor as storage device.but output of  the generator is 3v~6v DC.how i can regulate the output ≤5v?.i am looking for most simplest and cheapest method. can i use a resistor?

Question by vina1991 3 years ago  |  last reply 3 years ago


Voltage Regulator Question? Answered

Hi Guys, Looking a bit into voltage regulators. When I'm looking at the wiring diagrams on the datasheets, most of them indicate that it requires a 30V+ish input voltage to work. I was hoping to get a small adjustable voltage regulator to run off the 12v range. I really don't need anything over 12volts anyway. Can I get this to work or do I have to find a power supply capable of providing 30V+ for the voltage regulator? I was looking at models such as the lm117 if it helps. Also, If I do need 30v+, where can you suggest I get that kind of power supply? I usually use 12v wall adapters. Thanks!

Question by transistorguy 6 years ago  |  last reply 6 years ago


voltage regulators and supercaps? Answered

I have 12 .22F 5 volt supercapacitors that i bought recently. Ive been thinking about making something like the Mintyboost from Adafruit but am unsure on how to do it with supercaps. Any help is appreciated as this is stumping me pretty well. thanks, bud

Question by budhaztm 6 years ago  |  last reply 6 years ago


Voltage Regulator circuit

I am trying to power Bluetooth module and the Arduino using a 9V battery. So tried to use a voltage regulator (KA7805) with 25volt 100miro farad and 63V 1 micro farad capacitors. I checked the circuit connecting these components using multimeter, it showed 5.06V as the output. But the problem comes when I connect the Bluetooth module to this output, which turns off after quickly. I checked the voltage at the bluetooth which is reducing quickly from 5V-2.5V in a matter of seconds and since the operating voltage of Bluetooth module HC-05 is 3.6V-7V, it turns off. I am not clear why this circuit behaving this way. Same output when I connected to the Arduino, it works seamlessly. Please let me know what are the mistakes that I need to rectify for this work. Thanks in advance

Topic by Bhanu Kishan 4 years ago


Rules and Regulations are where?.

I am new! I am New! And when I say new I mean I am 40 years old and only recently embraced the computer and thuslynthe intro-web. Although my embrace of said tea is like those crazy hugs where people kind of stick their buts out and break off quickly. Don't think I am some guy that has lived under a phone book all my life. I have used computers before but never in my spare time. so forgive me if what I am looking for is simply found. The reason I ask is I "did" belong to an interesting site but I am on restriction for recommending a different web site. The web site was not even in the same field but anyways. I am really digging this site and don't want to screw it up. Like right their I do use more colorful language from time to time.. Thank you for your time.

Question by AlexD164 3 years ago  |  last reply 3 years ago


Is there a difference between a 7805 regulator and a LM7805? Answered

Lm7805 http://www.sparkfun.com/products/107 7805 http://www.radioshack.com/product/index.jsp?productId=2062599#

Question by Munchys 8 years ago  |  last reply 4 years ago


Portable 3.3v regulator for a 9 volt battery? Answered

I've seen a great deal of portable breadboard PSU's that output 5 volts from a 9 volt battery, and I find these fantastic! However, I was curious...is there any way to refine this futher down to get a steady 3.3 volts? I would like it to be something close to the system that sath02 has made here as it not only better suites my nees, but makes sense to me. Thanks in advance!

Question by DoctorWoo 6 years ago  |  last reply 6 years ago


Need a 100v voltage regulator?

So what I am trying to do is make a variable power supply from a computer PSU, I've done thise before minus the variable part. I need a voltage regulator that will limit 200 or more volts to 100 volts DC. I also need different variable voltage regulator that will allow me to adjust this from 0 to 100 volts, they usually have a circuit in the datasheet that uses some resistors and a potentiometer. So, are there voltage regulators like this? If not what is another way to do it?

Question by XOIIO 5 years ago  |  last reply 5 years ago


I'm using a 5V boost regulator?

To charge a cell phone battery.  BUT maximum current is 200 mA.  That's not enough current I'm assuming, right?  I need a continuous output of 5V but my students are most likely not going to get 5V from a shake charger (neodymium magnets going in and out through a coil of wire) which is why I was going to use a LM7805 but that needs 3 volts more than the output voltage.  Any suggestions??  Thank you!

Question by mckywer 7 years ago  |  last reply 7 years ago


How do you test a dc voltage regulator?

I have a dc volt regulator that reduces the voltage to around 12 volts. How can I tell if it is good or not?

Question by DELETED_afw11 9 years ago  |  last reply 6 years ago


Variable Voltage Regulators with + and - 12v input? Answered

Hi, I have put one of these together for an ATX power supply and have come across something that I might be getting wrong.... In mocking up the LM317 circuit in breadboard (standar one found everywhere on line and on the LM317 pages), I have got the thing metering -11v to +11v??? I am using one of the black ground wires of the PSU on the black side of the volt meter, but cant figure out why I am not just getting positive voltages??? Could the diode be faulty? Or is this in fact correct? Any help appreciated...

Question by lone_viper 7 years ago  |  last reply 7 years ago


I wan't to know about the speed regulating device known as a governor.

It's also known as the centrifugal governor.It is used in vehicle engines.It's function is to limit the speed of a mechanically driven device.

Question by ammarasheed 9 years ago  |  last reply 9 years ago



how do i use a 7805 voltage regulator with 6 volts power supply? Answered

How do i use a 7805 voltage regulator with a 6 volts power supply?

Question by imakethings 9 years ago  |  last reply 9 years ago


Why do my lm317T and lm78XX regulators die so easily? Answered

While using my last 7808 voltage regulator as nothing more than a voltage reference for a breadboarded linear power supply design, I noticed that after a few small modifications, that the 7808 was no longer outputting 8V, and was instead floating 14.8V (kinda close to the +15V supply rail). At no point did the regulator overheat, and it was simply connected to the a 200K potentiometer to ground and a noninverting input of a LT1112. In the past, I have killed at least 3 LM317T regulators in my velleman 3-in-1 lab thingy, (it is a relatively simple circuit and was the first board I have ever fully reverse engineered.) The heatsink never did get too hot, but I used to always connect heavy loads to it that caused the overload lamp to come on. That LED was basically in series with a large resistor to the input of the LM317 so when the LED has enough bias voltage, it comes on when around 1A is being pulled. Anyways, I have killed countless other small 78xx regulators, one way or another, and even made some of them literally explode right away. (generally by getting the pinout wrong.) I blow up these regulators so commonly I even have video evidence lol! click to around 3:30 for the FAIL! https://www.youtube.com/watch?v=lPHHvVTVbwM So is it just me and my luck, or are these regulators which supposedly have all sorts of thermal protection, current limiting, and short circuit protection just not as rugged as they seem they should be?

Question by -max- 3 years ago  |  last reply 3 years ago


12v to 6v voltage regulator at about 15 amps

Hi, i have a 1963 VW bug that is very stock, but the 6v lights just dont work very well (dim at idle, then not too bright at speed) it is very simple to use a later 12v generator and then swap out all the lights, battery, coil and relays and it works great. BUT i have a 6v wiper motor and also a 6v gasoline heater that i will need to keep at 6v (the 12v parts are just not available or too expensive) I have found an article that recommends building a cheap voltage regulator using a 7806, ( 6 volt, 1 amp regulator) and 2 1uF 35v tantalum capacitors, then a NPN transistor which the original poster says is a 2N5881 npn transistor. here is the scematic. the pdf article is attached and the link to the original article is here http://www.studebaker-info.org/tech/6-12V/6-12-6.html  The questions i have 1. what is a 2n5881 been replaced as? i cannot find it at jameco and the original posted doesn't give any specs for it. 2. how would i "pump up" the amps available from 10 to anything else (looking for about 15 amps) thinking that the npn transistor is the key but i am new to this and wouldn't even begin to know where to look. 3. what happens if any item fails? can i put some sort of safety into this so it quits rather than passing any addition voltage through additional info the heater runs at about 85 watts so 85 watts / 6volts = 14.616 amps  the wipers run at much less than that so building 2 of this would work great.  Any ideas? Thanks in advance for any insight to this 

Topic by starvin 7 years ago  |  last reply 7 years ago


Pls Help me!!!can i hold 12v dc and 24v dc? can i be grounded?

Pls Help me!!!can i hold 12v dc and 24v dc? can i be grounded?

Question by axdsqzwer 7 years ago  |  last reply 4 months ago


i have 12v 1A dc voltage supply from an adapter and 5v 0.25amp bldc motor so how to reduce voltage and power my motor?

Input 12v/1A dc power supply from AC to dc adapter ..  and want power a 5v .25 A brushless dc motor ... so want a stable and reliable dc voltage reducing circuit which will not burn out if used for long time.

Question by RajeshM64 2 years ago  |  last reply 2 years ago


Where find 5v regulators?

Hi!Where can i find 5v or 12v voltage regulators?

Question by ondrikczech 6 years ago  |  last reply 6 years ago


PYROGRAPHIC TOOL HEAT REGULATOR

How Can I make a Homemade pyrographic heat regulator using salvaged parts??

Topic by smallludwig2 11 years ago


Use a Co2 regulator for air?

Can I use a Co2 regulator to regulate high pressure air.  I am trying to build a high pressure system using a scuba tank or paintball/airsoft tank to operate air tools, pressurize pipes, fill tires, inflate balloons, dust work areas and computers, etcetera.  There are C02 regulators but not many 'air' regulators.  I just want to use air and not Co2.

Question by RandallIja 9 years ago  |  last reply 9 years ago


Help Making 6V regulator?

I need to power one of my projects for which I need a power source. I require 6V,which will require a lot of batteries. So, I decided to make a regulator and supply it through my 12V DC transformer. Please if any one of you can give me a schematic of the same I will be gratefull.

Question by pranjal12 6 years ago  |  last reply 6 years ago


Will a switching regulator charge an Ipod? Answered

I have a 16 gb Ipod Touch and I wanted to be able to charge it from an old laptop battery that is 14 volts. I did not like the idea of using a 7805 because it is so wasteful, so I was thinking of using a switching regulator like this one because it has an efficiency of 85% @ 14 volts. http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name;=LM2591HVT-5.0-ND Something in me is just worried that because its switching on and off really fast to achieve the voltage that it will not work for charging my Ipod, so I came here to ask "will it work and is it the best option?"

Question by flybye22 9 years ago  |  last reply 9 years ago


Voltage regulator for solar panel

I have built a solar panel as a fun little project, now it has come upon a big problem. The solar cells that I am using seem to have a higher amperage output and a lower voltage output in high intensity sun while having a high voltage and low amperage output in medium and low intensity sun. This poses a problem as my batteries were able to recharge during late winter and early spring but now are not able to recharge when there is the most energy to be captured during the summer. The average voltage during high intensity is about 11 while the voltage during medium or low is around 12.5 and 13. I want to know if there is a way to create a transformer to step up the voltage or create a voltage regulator that can withstand 13 amps so the battery can recharge properly. A link or any suggestions would help.

Topic by menace 9 years ago


Regulator for disposable oxygen tanks? Answered

Does anyone know how I can get (or make) one of the regulator / valve things that screws on to a disposable oxygen tank? I would use the regulator from a propane torch but it has to have left hand threads. All the ones on Google shopping and Ebay cost like $40 and I realy don't want to pay that much, I'm thinking more like $10 or $15. I could use a Nitrous Oxide dispenser like the ones used for making whipped cream instead if anyone knows how to get or make one for the same price.

Question by Jaycub 8 years ago  |  last reply 4 years ago


voltage regulators vs resistors? Answered

What are the benefits of voltage regulators over resistors and vice versa? why to use voltage regulators if resistors can limit the voltage?

Question by Ahtasham Ahmad Mohtashim 5 years ago  |  last reply 3 years ago


How to make Voltage regulators

I would like to know how to make a voltage regulator for an old generator. The regulator has stopped working and is hard to replace. I need an out´put of 120 volts with 15000 watts and ofcourse the 50-60 hertz. Thanx for your time

Question by Soochi 6 months ago  |  last reply 6 months ago


3 volt voltage regulators?

Hi,I need a 3 volt voltage regulator,1 ampere(or lower).I tried looking for Lm 7803 but couldn't find it any local shops.Anyother alternatives?

Question by Adarsh_tronix 6 years ago  |  last reply 3 years ago


how to make a thermo regulator? Answered

I want to heat water between 20c -40c

Question by Ashravin90 6 years ago  |  last reply 6 years ago


6v 0.5a voltage regulator?

I need to drop down the voltage from 12v 1a to 6v 0.5a for a project but i dont know how to do this please help me !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Question by Andrew_48 8 years ago  |  last reply 6 years ago


Where is the 3.3V regulator on this board?

I need a 3.3V for one of my projects and decided to scavenge one from an old Arduino clone I had lying around. Only problem is I can't figure out where the 3.3V regulator is!! The board has a 3.3v pin and I've also measured a steady 3.3V output using a multimeter but all I can see on the board is a 78M05 and  a diode. I've uploaded a picture of an original Arduino Uno board I have for comparision. The 3.3v regulator on that one is pretty easy to find. Any help in finding the 3.3v regulator will be appreciated. Thanks.  

Question by newbie007 4 years ago  |  last reply 4 years ago


Battery charger regulator question?

I've got a 40 amp 12 volt  RV power supply that I want turn into a battery charger.  Anyone got any ideas about how to regulate the current so it doesn't cook the batteries?? Thanks 

Question by jimnjo 9 years ago  |  last reply 9 years ago


A 12v Regulator in a USB hub?

I havea spare USB hub and it's not used. I wanted to take it apart and take the regulator out of it. It has a part number: PJ1084/CM 1B1. After Googling the part number I've found that it's a 12v 5A regulator, why? The mains adapter with it is only 7.5v, so where does 12V come from, the only thing that I know is 12V is the PS2, and this is definetly not for that.

Topic by Josho 11 years ago  |  last reply 11 years ago


Voltage regulator for trailer brakes

Im planning on building a motorized trailer dolly for my travel trailer, however i want to make a dead mans switch for the trailer brakes.  I was wondering if I took apart an old cordless drill if I could use the trigger as a voltage regulator to regulate the voltage to the trailer brake system.  Without getting into specifics of how it will connect to the regulator, I figure I would have like a bike brake handle that while applied the trailer brakes would be off, but if released that the trailer brakes would be applied incase the trailer started to roll away from you. Any suggestions other than "Go buy a trailer brake controller" would be appreciated! :)

Topic by Thunderbone 1 year ago  |  last reply 1 year ago


Motorcycle regulator wire burning

I have a xj600 pre div, been stood for few months, I started her up other day and after ten mins ticking over I noticed the wires coming from/to the regulator/rectifier started to burn....What could be the causes??? And what can I do To fix please... Thanks....

Topic by AlanW131 3 months ago  |  last reply 3 months ago


Zener diode Regulator Assy

I am in need of assitance for assembly instructions for building a 5V power supply from a 12v power supply using axial components. I am not sure of the orientation & solder method of components. Thanks for any help. MCD

Topic by mcoanarmen 10 years ago  |  last reply 10 years ago


Voltage regulator Design Problem?

 Ah, voltage regulators. Easy Right! Not this one. I am making a voltage regulator like for an automobile regulator for a DC generator. (I'm replacing the old DC generator regulator on Pre 60's cars) A battery is charged from a winding on a Generator  (20V @ 60 Amps) A voltage sensor on the battery voltage turns on and off a switch driving the Field winding. The Field winding basically "turns on and off" the generator output. The battery is connected directly to the generator. (Why  and Why not is coming up) But when the Genrator's output is lower than the Battery voltage, current will flow back from the battery to the generator winding and discharge the Battery. So I need some isolation between the generator output and the battery. Alternators are easy since it has a bridge onthe output keeping the current from flowing backwards. Old regulators used a relay which burned out sooner or later. So easy, use a diode right? Just put a diode inseries with the generator to the batery. By the way, the "open circuit" voltage on a generator is about 200VDC No! The best diode I can find has a .7V drop at 60 Amps which is 42 Watts of heat to dissipate. Ahhh, so use a FET, They can get down into the milliOhms right? Except for the reverse polarity (and ESD) protecton diode always across the FETs defeat the purpose of a reverse polarity switch. So who out there is smarter than me? What goes inthe box marked ?? Any solutions accepted. Ungefahrt (now neither young or fast)

Question by ungefahrt 6 years ago  |  last reply 6 years ago