Lab power supply - Page 1
Forum section: electronics / projects

author: lastdeath
author_rank: Contributor
timestamp: November 29, 2012, 07:52:00 pm
content: Hi guys, i just started a eletronics classes, and the teacher asked to make a power supply, with +15v and -15v. Can someone send me a power supply design with theses specs? i want a power supply that i can choose the output voltage, with a led indicator and fuse to protection.sorry my english.

author: Kremmen
author_rank: Super Contributor
timestamp: November 29, 2012, 08:01:57 pm
content: Well... no. Where would the fun be in doing that? What is your own thinking - why did the teacher give you this assignment. 2 guesses: either go and buy one or _design_ one. Now i think it was the latter. But do correct me if i was wrong.If you ask specific questions i am sure there are many here who are willing to answer. But it is you who are studying so you should understand what you are doing, not just copy a design someone else made.

author: nctnico
author_rank: Super Contributor
timestamp: November 29, 2012, 08:09:59 pm
content: First Google for 'voltage regulator'. And then look for application notes.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 29, 2012, 08:33:14 pm
content: here kid, to your specification...Please Check My Simple PSU Circuitthat was when your "uncle" learn how to do it few months back, draw crappy schematics and stuffs... you will need a bit of translation since the schematics are so crappy, but when you have finished, you'll learn to appreciate what it can do, as your teacher has foreseen perharps. now take that away to your bench and study it, pass the exam and be a good engineer

author: Simon
author_rank: Unknown
timestamp: November 29, 2012, 11:09:48 pm
content: Quote from: AcHmed99 on November 29, 2012, 10:45:04 pmDitto

author: Smokey
author_rank: Super Contributor
timestamp: November 30, 2012, 01:22:18 am
content: One detailed flux capacitor schematic coming up. You'll have to copy it though because all I have is this image. Sorry.Edit:Oh I forgot about the DeLorean.. here you go...http://www.autotrader.com/cars-for-sale/vehicledetails.xhtml?zip=90210&endYear=2013&startYear=1981&makeCode1=DELOREAN&sellerTypes=b&searchRadius=0&mmt=%5BDELOREAN%5B%5D%5B%5D%5D&listingId=328239711&Log=0

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 30, 2012, 03:03:04 am
content: nevermind them kid. they liked to ask such question when they were in school, thats why they are here keep asking but no answer. why? they thinked too much complicated where the answer is obvious. fill a cap with no-water flux and inject it with magic voltage they should get flux capacitor and smash your car with lorry you'll get that horizontal wheels delorean, connect the HV cable left to right then boom off you go, you must also design a helmet that connect left to right. your question is a valid one, and also dont forget to look up LM317 and LM337 datasheet, they are Hollywood superstar in Silicon Valley.

author: nerdyHippy
author_rank: Contributor
timestamp: November 30, 2012, 03:58:47 am
content: I designed such a supply for you. It is battery operated. Each battery in the schematic represents a 1.5V cell; be sure to use fresh ones otherwise the voltage will drop lower than ±15V.

author: lastdeath
author_rank: Contributor
timestamp: November 30, 2012, 06:31:50 am
content: lol, i didnt expect so many trolls, i just asked because the objective of this power supply is use in our labs, which starts monday, the teacher asked us to search online and build a power supply, the objective is the build part and dont the scheme... so, i thought that asking here, i could get a good design for a good power supply. But thanks anyway, i will google for power supply and get one.

author: Shuggsy
author_rank: Regular Contributor
timestamp: November 30, 2012, 06:57:07 am
content: Quote from: lastdeath on November 30, 2012, 06:31:50 amWhat do you have as the source for the power supply? Do you have positive and negative DC sources? If so, you could make a quite simple supply with linear regulators like the LM317 for the +15 and LM337 for the -15. Any specs like required output current? Adjustable voltage levels? Current-limiting?Googling will likely get you some simple kits you can build up. for example, there's a breadboard power supply kit that can go up to ~19.5V DC (given a 20V DC input) on Ladyada.net.

author: lastdeath
author_rank: Contributor
timestamp: November 30, 2012, 08:46:30 am
content: Quote from: Shuggsy on November 30, 2012, 06:57:07 ami found this scheme on the net, and i think i will build it, but i need put fuse to protect, leds to show when is on, in this scheme i can control the voltage, but i want a better method to do it, i ill build this inside of a wood box, so if is possible i want control the voltage externally.http://www.te1.com.br/wp-content/uploads/2012/03/337_317_fonte_simetrica_ajustavel_esquema.pngthe source will be the power line, in this case a 120V 60hz voltage. Dont need current control, just the voltage is good. i will use a 120-15 transformer with the middle tap to 0v.again sorry for the english.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 30, 2012, 09:05:30 am
content: Quote from: lastdeath on November 30, 2012, 06:31:50 amno offense kid, but to get a good design at beginner level uncle can only give you some advice. either buy a branded ready made one, or spend more than that in term of time and money, buy your parts and start tinkering, regardless whether you want to make your own novel design, or if you are getting a good schematics from the net that you can slap in.

author: LEECH666
author_rank: Frequent Contributor
timestamp: November 30, 2012, 09:41:44 am
content: Im going to quote myself from a post a while back:Quote from: LEECH666 on July 02, 2012, 11:00:53 am

author: c4757p
author_rank: Super Contributor
timestamp: November 30, 2012, 04:49:00 pm
content: AcHmed99, considering he said "sorry my english", I wouldn't be surprised if the phrasing was unintentional. I try to avoid tearing new assholes for people who include English disclaimers until I'm damn sure I know what they meant.lastdeath, at least the responses were funny. I don't mind people mocking me if they at least bother to make it funny so we both get something out of it

author: Mechatrommer
author_rank: Super Contributor
timestamp: December 01, 2012, 03:45:42 am
content: Quote from: c4757p on November 30, 2012, 04:49:00 pmbrilliant! it should be reflected in my signature by now.