A voltage regulator is a system designed to automatically maintain a constant voltage. A voltage regulator may use a simple feed-forward design or may include negative feedback. It may use an electromechanical mechanism, or electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.
Electronic voltage regulators are found in devices such as computer power supplies where they stabilize the DC voltages used by the processor and other elements. In automobile alternators and central power station generator plants, voltage regulators control the output of the plant. In an electric power distribution system, voltage regulators may be installed at a substation or along distribution lines so that all customers receive steady voltage independent of how much power is drawn from the line.
http://img715.imageshack.us/img715/2721/capturehoq.png
I am having a bit of trouble understanding this circuit. My textbook is pretty vague on the topic of three terminal voltage regulators, really only emphasizing on the LM317. For this circuit, is it necessary to know +Vcc , or V_load...
Specifically, this switching reg as an example, though these questions may apply to others: http://www.sparkfun.com/datasheets/IC/MC34063A.pdf
Switching regulators weren't covered very well in my class, and they're significantly more complicated than linear regulators (which also makes them a...
I am trying to design a circuit that has 20 mA acoss an LED, I had been advised I could use a voltage regulator to keep the current at 20 mA. However, I am not exactly sure as to how to set up the circuit. Would I set it up so that it would maintain a voltage and then run that voltage across a...
Why does LM7805 and LM7809 give less voltage? Practically LM7805 is giving 4.9V instead of 5 and 7809 is giving 8.8V. Can anyone please tell me the reason?
Can anyone tell me which voltage regulator is better to use for power supply. LM140, LM340 or LM78xx series? I want to know which one is most economical and easily availabe. Thankyou
I want to make a power supply which gives DC voltage from -17V to +17 volt, i.e of both polarities. Someone please tell me which voltage regulator is easiest and most appropiate to use? Thankyou!
I have a small e-reader that I use for long flights and random opportunities to kill time. It's a great little device but recently it's been having charging problems. I narrowed down the problem to a voltage regulator. It seems that when I lift the ground the unit will work fine through usb...
Referring to: http://www.cunicocorp.com/images/2250.gif
I'm looking at some of the regulator/shut-off valves in use today, and as far as I can tell, every one of them kind of redirects the gas as they go through the plug in an awkward and flow-disturbing pattern.
As with something as...
My teacher was talking about power supply voltage regulators.
I cannot get why does a zener diode regulator's output voltage drops after the load current through it exceeds some critical current?
thanks in advance :smile:
Homework Statement
revered members,
this circuit i have attached is for voltage regulation using zener diode.
applying kirchhoffs current law i get current through resistance R is IR=IZ+ IL
And the voltage drop across the resistance R is V-VOUT
HOW this equation of voltage drop is...
Need to create voltage regulator, using a sinusodial wave and a 12 V dc source in series and a load resistor 200 ohms. Voltage output must be 5.7
I Can use op amps, resistors, capacitors, and inductors
I have been working at this for weeks and I can not find any information on how to...
This is a general question. When using the optimal method to design a controller, specifically a linear quadratic regulator, you usually have a state-space representation of a system, and a cost function to minimize.
The cost function usually takes the (quadratic) form:
I don't...
Hey all,
I am working on a 0-40V variable power supply right now, and while the power supply is working I am wondering if it is in danger of overheating. I am using a LM317 with a 0-5k potentiometer between adjust and ground, and a 165ohm resistor between output and adjust. Input is regulated...
Hello all.
I was just wondering if it is possible to use an inverting opamp configuration with feedback to regulate an output voltage V0 without the use of BJT's?
For example, the following sketch:
http://img411.imageshack.us/img411/2389/opamp.png
V0 = Vs * (R1-R2) /2R1
Mathematically, V0...
I have a 2-12 volt motor circuit with a max amperage load of 24 amps. The cars charging system can fluctuate between 12.2 and 14.7 volts. This causes the speed of the motors to fluctuate too much. The problem I am having is I would like to limit the voltage on the power supply line to these...
Hi!
I'm working on designing my own voltage regulator circuit by using LM7805.
From what I found from website the capacitors connected parallel between common leg and input and common leg and output,its values varies from one website to another.
Actually how to determine what capacitor...
Yeah I know the title sounds strange. But here is my situation:
I have a circuit that is powered by the USB port (Max 500mA Draw @ 5V). On my circuit board is divided into two sections, one that contains the digital logic and other stuff which i estimate can draw up to 200mA worse case...
Hi There,
I have a CCR (High Power) to feed current into a airfield lightning serial circuit which is having a lot of troubles trying to maintaing the current regulation.
Basically the problem is that once the CCR is set up to highest step (Step 5: 6.6 A) with a maximum load (PF=0.98), the...
Hi Everyone,
I need to design an adjustable voltage regulator without using an IC. Does anybody could give me a source that can help me?
Input will vary between 10-15 volts... And output will be adjustable between 4-6 volts.
Line and Load regulations must be around %1
Need your help...
What is a PFC pre-regulator?
What is the use of it?
What is the circuit diagram in it when using buck converter?
Please post some link about pre-regulator in buck converter.
Thank you.:smile:
The voltage regulator have 3 legs, 2 for input and one for output to make a constant voltage.
I was wondering if this is possible?
2 x input of 12v and can the output be 24v or only under 12v?
thanks
http://img104.imageshack.us/img104/3557/1234uyq.jpg
Ok, there are a few calculations on this problem that I am having difficulty with. This is a past homework assignment which is why the answers are filled in. They are all correct.
Anyways I approached the problem in this manner:
V...
Hi all, I am working on finding a programmable regulator circuit that can produce 0-12 volts for a power amplifier. It needs to be linear, with a DC input and control voltage so that a PC can be used to generate an input profile.
I am making a power supply and am using a lm338k to regulate a variable voltage from 2 to 30 volts. I also want to put in current limiting, preferably variable, up to 5 amps since that's what the lm338k is rated at. Since the resistances in the current limiting circuit need to vary when the...
So far I've seen that a pressure regulator regulates the pressure from upstream to required pressure downstream and that a flow regulator regulates the flowrate, obviously.
But, theoretically, doesn't one regulate the pressure to induce a specific flowrate? what is the actual difference...
I am to design a simple voltage regulator(resistors only) to deliver 7.00 volts to a load with a 10v power supply. The circuit will be 1 resistor in series with two parallel resistors. The last parallel resistor being Rload (which can vary from 1000 to 1500 ohms).
Through experiment, I found...
Hi,
My problem is very simple, I have a project in which I have to design a voltage regulator out of discrete BJTs, Zeners and resistors etc. the only limitation is that I cannot use an IC. I would prefer not using a zener because i would like to make the output variable through a voltage...
hey guys, I've got to make a voltage regulator for a uni project. it has to use hysterisis and produce 9v out from a 16Vrms AC powerpack over a 15 ohm load. It also needs overload protection, I've drawn up the attached circuit, i think it will work and filled in some of the values i know but I...
I'm working on a design that requires me to control the output voltage on a line that will be used to drive a motor or other item.
http://www.az-prod.com/vregcheck.jpg"
The above link goes to the schematic I have in mind. Please ignore the MOSFET symbols, I'm pretty sure I used a...
I need to calculate the spring force required to make a back pressure regulator for fluid control the back pressure must exceed 3bar to open the ball valve the flow rate is 82mls/per min. the bore dia of the inlet is 2 mm dia. any help greatly appreciated
Could anybody please assist me.
I need to regulate 12 volts dc from a car battery down to 1.24 volts dc yet I still need to be able to draw 12 - 15 amps. Ideally I would like to be able to adjust the voltage. Does anybody have any ideas how I will be able to achieve this & if so, what...
Hi experts! I want to incorporate a 5v booster and regulator into my circuit so that if people use 4 alkaline batteries or 4 nimh batteries it will always be 5v. Is there an easy way to do this? For example an IC and minimum external components rather than this...
I'm giving it exactly 5 volts directly from a DC Power Supply and the output voltage should be 3.3V but it's not. I don't even have anything connected to the output pin of the regulator (holding it in my hand).
It seems if
V_in < 1.5V, V_out = about 0 plus a couple millivolts
V_in >= 1.5V...
This may be a dumb question but I guess it won't hurt to ask. Is there a reason to use a voltage regulator to obtain a lower voltage from a certain set power supply voltage over using a voltage divider? I guess I'm talking low voltage applications in circuits not high power electronics.
[SOLVED] Voltage regulator
Homework Statement
This isn't a homework or coursework question. It's just a general question. I have a circuit with a 15V power supply. The output has to be 12V. I've inserted a blocking diode to prevent current flowing in the opposite direction.
The problem I'm...
I was going to use a +5V Fixed-Voltage Regulator 7805, for a project until I noticed that I need 2 amps and the 7805 can supply at max 1 amp. what can I do?
Hello All,
Now I'm looking for a good way to power all the chips on the control board I'm designing. It will be powered by two rechargeable 9V batteries in series for a total input voltage of about ~14V.
The interesting thing is that the chips I am using all require a wide range of voltage...
X is a smooth quasi-projective variety over Q.
Beilinson's regulator map is a map from the motivic cohomology H to the Deligne cohomology H_D. Originally the motivic cohomology was defined by Beilinson as an eigenspace of an Adams operation on an algebraic K-group. Bloch (or Levine or someone...
hi guys
need some component that will take in 12 VDC and put out a negative 5V AND a positive 5V - just a very simple component - a part number would be great - thanks
Hi,
I started a project a few months ago to replace the voltage regulator on my car's alternator but I had to stop due to lack of knowledge and testing ideas.
I've since learned a lot more about electronics and have decided to pick it up again. Straight away I've made a design change after...
Looking to drop a 10v Li-on battery to 6v DC. What is the most efficient way without to much wasted power. Adjustable voltage regulator? diodes?,
something else? needs to be small. Thanks
I need to design a voltage regulator circuit to provide a constant voltage of 5V to a load from a variable supply voltage. The load current carries from 0 to 100 mA and the source voltage varies from 8 to 10 V. You may assume that ideal Zener diodes are available. Resistors of any value can...
Hi,
I'm using an LM2672 Fixed 5V (up to 1A load) regulator in a project. The regulator has specific requirements for the input capacitor ie low ESR, RMS current rating >= 1/2 DC load current, at least 15uF if solid tantalum is used. The input voltage for the board is 12V (from an external ac...
Hello all,
I am looking to build a small varible voltage regulator that I can control from the inside my vehichle, that will allow me to control the voltage of my 320 Amp Leece Neville stand alone alternator... Currently I use this alternator to power my amplifiers that will handle up to...
I've recently purchased a Magnavox 15" LCD-TV {15MF400T/37}
which requires 12 volt, 3.5 Amp, DC input.
I want to use this TV in my RV - on a Standard 12 volt,
Deep Cycle, Vehicle Electrical System - where voltage can
vary from 10 - 15 volts depending on the state of discharge
or...
Hell oI am a car audio installer. we have a incar video monitor that has a voltage limitation of 12v +/- 15%. problem that arises is that below say 11.5 it won't turn on, if above say 13.8 It shuts off, If the voltage is low it gets lines running through it, if there is enough to allow it to...