Regulator Definition and 140 Threads

I have two questions. 1. A lot of voltage dividers are wired up like this: Is there any reason why they can't be wired up like below? 2. When should a voltage regulator be used instead of a voltage divider?

First time posting a problem on here. Be gentle on me :) So I ran into this problem when I was testing the power supply block for my senior project.I attached a pic...

Homework Statement Create a 15V regulated power supply capable of providing a maximum load current of 25 mA. Circuit looks like this: http://i.imgur.com/fMtscbG.png?1ILmax (maximum load resistance) = 25mA Izt (test current) = 20mA Izk (knee current) = 25mA rz = 11 Ω Vz (nominal zener voltage...

Homework Statement The diagram: http://images.fr1ckfr4ck.fastmail.fm/probB.jpg These zener diodes; Have a test current of 5mA when 6.8V is applied (V_z=6.8V, I_z=5mA) Have an incremental resistance (r_z) of 20 ohms Knee current (I_zk) is 0.2mA Calculate the output voltage...

Hi all, I need a model of a pneumatic pressure regulator. The model should be as simplest as possible and use an optimization solver to identify the regulator parameters in order to fit the performance I find in the datasheet of a commercial pressure regulator. I have already done a model...

I want to make a .00 to 1.00 volt dc voltage regulator with a pot that goes full circle like 0 volt way to left and 1 volt way to the right I can either power this from a 1.5 AA battery or 12 volt car battery how is the best way to go about and what components would be needed? What I am trying...

I'm using a LM[Three-One-Seven] to regulate dc voltage output from mains power(240V ac). For PSPICE simulation, I was instructed to use an ideal OpAmp and Darlington BJT to model the IC in PSPICE. I came up with the following model, which satisfies the equation Vo=Vref(1 + RL/RH), where Vref =...

I am trying to replace a voltage regulator with an, as of yet, unavailable LM4040BIZ-10.0. I would like to keep the same pin design, but can work with a modified connection if I must. I am not a hobbyist, just a guy that likes to keep things working. I went through a few datasheets and must...

Hi, Thank you for all the help you've been providing, here I go again with another Electrical question: I am designing a PCB and I need a voltage regulator similar to this: http://img191.imageshack.us/img191/6499/n7p3.png but I don't want to use the LM7805 and the LM7905. I am trying...

Anyone know what is the major weakness of a Buck Regulator that compared with a Linear Regulator? Thanks.

Consider a DC motor, being switched by a H bridge that is controlled by a PI current regulator. As long as the error (SetCurrent-Current) is positive everything is good. However, when this goes negative we have a problem as you couldn't set a negative duty cycle. How is this solved in...

Hi, I have a very basic conceptual question. I have a system (eg. inverted pendulum) that I want to control. So I need to build a controller. That is clear. If I understand it well, I have minimally two separate options: 1 - use PID regulator/controller 2 - analyze the system, linearize it...

I have a self-venting single-stage pressure-reducing regulator that takes ~2500 psig and steps it down to ~1500 psig (here is a link with the specific details of the hardware if interested: http://www.items.se/Dokument/44-1300_10061107.PDF). I experienced some odd behavior recently where the...

So for a power supply project I need a voltage regulator giving me a positive output at around 40v. Obsessively you can not buy these, So i am useing a circuit which consists of a resistor, npn transistor, and zener diode. the positive input goes to the collector of the transistor and through...

Hello, I am working on a project and having an issue that I just ran into. I want the user to be able to regulate pressure from 0-60 psig max. When I start specifying the pressure regulators, found that they're sold with maximum outlet range either 0-50 psig and 0-100 psig. so I figured to...

So I need to use this LM117t 3.3v voltage regulator and I asumed the pins were the same as most regulators where you have in/ground/ and out. But it is not working that way, does anyone know the in and outs of this regulator or have an alternative?

Hi, on page 23 of this datasheet (http://www.fairchildsemi.com/ds/LM/LM7805.pdf) the top figure 10 shows a setup for a fixed output regulator, for example suitable for logic chips which need a steady 5V. I was wondering how critical the values of capacitance were for C1 especially and also C0...

The above (top) design is one for a adjustable regulated voltage using an IC. The bottom schematic is the actual design of the IC regulator. My question is, am I missing an obvious way to derive the relationship for Vo? How does this design work, anyway? I figured it had something to do...

Hi Folks, I have designed a rectifier and a regulator as independent entities. Both of these blocks are working fine when simulated in virtuoso independently. But when I integrate them, i.e when I connect regulator to rectifier, I am unable to see regulated output. I have attached the...

18v drill battery to 5v regulator?? Hi I have been doing a bit of research but am still a little unsure, I am trying to charge an iPhone from a dewalt drill battery, What I have so far is that the iPhone is a 5v 1000ma supply And the dewalt battery is 18v lithium ion Can I use a 7805...

Hi everyone, I want to understand how to decide what type of regulator I need to use in a circuit. I believe it will take much time to learn it totally but as a first step I am going to ask the differences between two regulator circuits. A circuit and the 5V regulator it uses can be seen...

Hi, I wanted to know if pressure regulators connected to gas cylinders provide constant outlet pressure, or provide constant pressure drop. Example of the regulator that might be used is this. http://secure.emiratesgas.com/eCom/details.asp?ProductID=ART01661_PR For instance, I have a...

Good day to all, was wondering how a pressure regulator doownstream will affect the flow rate of compressed air through a pipe. Anyone has any insights on this? the pressure regulator is to reduce the downstream pressure but I'm really confused how the flow will be affected. For instance, will...

The following link is a picture of my zener diode set up with variable load resistor. The Source is 15VDC and the first resistor is a constant 330 ohm. When I use 470ohm up to 15Kohm for the Load resistor RL, I get a 6V voltage drop across the diode. However, when I go down to 330 ohm for RL...

Hello, simple question here! When a voltage is regulated down or up in a circuit by, let's say a DC/DC converter, does the corresponding current increase or decrease respectively so that the system remains consistent with the laws of conservation of energy? In other words, I want to know...

Hi all! I am looking for a low cost power regulation solution. Simply put, I need to be able to give a system 12v and get outputs of 5V@2A and 6.5V@1A. I was thinking of using two of these with the output in parallel: http://australia.rs-online.com/web/p/switching-regulators/6727124/...

I wanted to know the function of a pressure regulator.. Am using one to control liquid flow rate. Here is my understanding- A pressure regulator can be connected across a valve. The pressure regulator maintains a constant "pressure drop" across the valve so if i set it to give a drop...

Hi all, I am trying to determine what approach to use to solve the following scenario: I have a pressure vessel with pressure P1 and volume V1. I have another vessel of pressure P2 and volume V2. Vessel #1 is supposed to be a high-pressure storage vessel and vessel #2 is supposed to be...

I'm working on a pneumatics project, which requires me to blast high pressure air through a set of solenoids. The problem I'm having is controlling the air pressure. The bottle of compressed air comes with around 2000 psi when full. I found out through trial and error that my solenoids refuse...

I have to design and construct an fuel system in one of my projects. In this project, I am designing fuel system which uses liquid fuel. The fuel is meant to be burnt in a gas turbine engine - thus the fuel will be injected in atomized form inside the combustion chamber. ___________ There is...

I have recently been experimenting with pressure to generate a mass flow and discovered something really bewildering. First let me explain the procedure. I use large stainless steel tanks filled to about 3/4 with water so there is a large enough capacity. I then pressurize the system with...

Dear Experts Lets say I have a power source of 9 volts. A 5v output voltage regulator is connected to this power supply. So, input 9 volts, output is regulated to 5volts constant. the output pin is connected to a battery with has a constant internal resistance. Does this mean, because...

I would like to inquire if a voltage regulator maybe used as a power supply to a system. I am not very familiar with EE stuffs so any help would be appreciated :) Our system consists of aluminum metal plates submerged in water. It needs to be supplied with 10A (DC) thru the portion of the...

I am working on a circuit. I have an IC bridge rectifier in place for ac to dc conversion at the proper voltage and amperage. I understand that the nte 7077 voltage regulator is for regulating voltage at 110 volts + or - .8 volts @ 1 amp max. This is a 5 pin IC regulator. I do not understand...

Hello. I asked this question because I am confused of the use of a reversed Zener Diode in voltage regulator even after I built the circuit using MultiSim. I don't understand why we should put a zener diode right there and how it works. I looked at the I-V plot of the Zener diode and I know...

I'm close to finishing my first 4-layer board. Initially, we felt that keeping the power supply as a separate unit would be better. This was because we wanted to avoid having heat on the main PCB - mostly because the area where the device is intended to be used is very hot and also quite dusty...

Hi all Here is the circuit that I will refer to: LINK : http://electronics-diy.com/lc_meter.php Ok my first question, Why do we need a voltage comparator (LM311) there? A voltage comparator compare the + and - voltages and output the difference?? What I want to do is, measure the inductance...

Hello our doctor gave us a project to design a power supply which looks like this http://i541.photobucket.com/albums/gg395/healing1000/powersupply.jpg however at the voltage regulator part (78xx and 79xx) there are 2 capacitors (the 2 on the right) which I don't know how to find their values...

I'm trying to see if charging large capacitor banks with a limited current LDO is feasible. If the capacitors draw current past the maximum current of the LDO, will the LDO become unstable or will it be current limited?

Homework Statement [PLAIN]http://img15.imageshack.us/img15/7379/unledtzc.png (The rods are of length L, there is no friction, massless rods, yadee yadee yada) At a certain angular speed \omega, the counterweight performs uniform circular motion. Show that \omega and \theta are related as...

First off, I'm not sure If the best place to post this would be in the ME or EE section. I'm basically looking for an inexpensive electronically controlled regulator. I want to hook it up to a standard propane tank that you would see on a grill and be able to control the output flow in...

Hello All, Simple question here. I have a microcontroller development board that plugs into the wall and has a garden variety LM7805 type 5V regulator on the board for powering the microcontroller and other peripherals. But also on this board is a header that allows the 5V from the board to...

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...