Power Supply for Home lab?

The Main reason folks build there own is first and formost for the experiance  (Kinda New EE 101) , it can teach you a whole load about electronics, OpAmps, Power Transistors, Feedback, Transient Response, Voltage References, Temperature stability to name just a few and at the end of it you have something usefull

The second reason is because you have a few of the expensive parts laying arround already and there just the ticket to build a PSU on a budget, Im talking about perhaps a transformer from an old AMP, got a box to put it in, have an LCD or LED display to show the volts and amps (Or an analogue one) etc. Then the cost is minimal for the rest and you still get the benefit of learning and something usefull

If the reason you need one is purly professional / Must have one for the hobby but are an experianced EE then yes, often much cheaper to simply buy one, albeit low end.

My series on building one is aimed at the folks wanting to learn and gain the experiance, and now im going to extend this to making it fully programable, even remotly so it will potentially be comparable with ones exceeding many hundreds of dollars.

Peter

You can't go wrong with an LM317 operating in Linear regulation mode!

Making its voltage programmable is as simple as incorporating a I2C/SPI/Serial controlled resistor.

Voltage regulators depend on good feedback!

Very true, and unless you have that feedback for the volts directly from the load or as close as possible (Banana Binding posts are often the nearest convienent spot), you will be prone to errors int he output, especially when drawing high currents, this is where using an LM317 and the like starts to fail from a design. There great chips, just sensing is local to the chip, not the load. For most purposes this is ok, but if you want a precision power supply, it wont work as well as could be needed

On S100 boards the voltage regulators are on every board (but the motherboard) for that purpose - to be close to their loads.

(Unlike a PC where it is inside the central power supply.)

On S100 boards the voltage regulators are on every board (but the motherboard) for that purpose - to be close to their loads.

(Unlike a PC where it is inside the central power supply.)

I was about to apologize for being off-topic(S-100 Kittens but thx to COMPACT(he/she made a good point(as did others about local(ized Regulation Currently I am using writing on this Blog-Thread on my Intel NUC i7RYH This NUC has a Power Brick(probably SMPS about 80x25x50mm in Size at 19V at#A b/c it is in use covering the Label Local regulation is occurring w/i the NUC b/c Even an old-Geezer like myself knows that nothing in the box runs anywhere near the High Voltage of 19VDC Far cry from my Original Personal Computer Imsai 8800 S-100 Computer which was pointed-out had Local Regulation on the Individual PC Boards via the likes of IC Voltage Regulators(ex 7805 in To-3?case 7812 7912-used for neg voltage swings of  RS-232RS-232 etc Have we Really come that Far Probably Not Every Situation is"unique to Us Beg Borrow Steal What ever works for You

COMPACT wrote>>...

Did you build your S100 computer in the 1970's?

And how about the really thick copper wires and giant filter capacitors that are larger than kittens for the +8V lines for the S100 bus!

My S100 computer was internet connected, is yours?

ELY reply>> S-100 in 1975(i Think?). Actually, I never used that Big Humongous Power Supply which I ordered and assembled. I continued to use the Original PSU (Transformer, Bridge Rectifier(s?) and Large Capacitors,etc). My S-100 "WAS" (past tense) never connected to the Internet. AL Gore did not invent it yet. LOL. I did have it connected to a Teletype ASR-38 (via Current-Loop). Still have both machines. Sentimental Value, I guess. I still have one Slide-Rule from my HS, college days.

But had given away other Slide Rule(s) and my HP-35 (gotten in 1972).

Another Time. Another Place.

BTW (to all on this Thread:) Could you guys/gals mind giving out your Location and possibly your Gender ( I love using Pronouns, like she/he)

ELY aka USCDADNYC [Male, lives in Queens, NY (NYC) USA] Two miles south of LGA airport.

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Ed,  my a Gender is to help others where I can and to have as much levity doing so.

Is LGA like a BGA?

I am transient so just don't put me through your speakers. I'm in one Location one moment and another the next!

To Compact:

Banana? I believe those male plugs that fit into Binding (female) Posts, were called "Banana Plugs." Unless you were talking about USCDADNYC personally. In that case I admit that I maybe considered a Banana. White on the Outside. Yellow on the Inside.

AAR LGA is LaGuardia Airport. I believe the Airline Travel Association(?) have 3-letter designations for Airports world-wide. IDK that BGA was the generic term for socket 1170, etc. Thx. Good to Know.

Compact wrote>>...

my a Gender is to help others where I can and to have as much levity doing so....

I am transient so just don't put me through your speakers. I'm in one Location

one moment and another the next!..

ELY Reply>> I guess that revealing your Gender would EnGender other consequences. I respect you for that. WRT Transients, are you like Surround Sound, you are Evertwhere. But remember the FireSign Theatre (Theater in US) who said "...how can you be in two places at once, if you are really Nowhere at All?"

[to others on this Thread/Blog] you can see why it might be better to include (our) Location. Theatre vs Theater? Or my use of Metric measures instead of the English (inches) Measurements.

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Correction."Yellow on the Outside. White on the Inside." Sorry. My Bad.

I would never call you the possibly derogatory term "Banana" although in New Zealand there are some persons who are proud to be called Bananas and have a dedicated organisation that has conferences.

http://www.goingbananas.org.nz/

If you are calling yourself a banana I'll call myself one too.

I'm yellow on the outside and inside and have many black bruises (due to illness).

I've seen Metre meters!

A USA resident using Metric - How rare!

It must get interesting when you're talking mils and mms (also pronounced mils).

Also did you know a US Pints are different to UK Pints!

I'm in two locations at the same time when you're not looking at me. If you try to look at me I'll suddenly be seen in either place (but since I'm transient I'm always moving around).

As is a US Gallon and a UK Gallon, threw me for years when trying to figure out my cars MPG....

Compact wrote>>...

I'm yellow on the outside and inside and have many black bruises (due to illness)...

.A USA resident using Metric - How rare!...

Also did you know a US Pints are different to UK Pints!

ELY reply>> Sorry about your Illness, I hope you are Better now. I am 64years old and am "Strong as Bull","Smell like one too" and "I am full of Bull". What killed Metric Conversion in USA was the (scientific) Calculators. I miss those Ms. Metric Calendar Pin-Ups where the girl in the Bikini's measurements were expressed in Metric units. I knew vaguely about the difference in US/UK Pints. But being a Tea-toltaller (sp?), I did not have many opportunities to "raise a Pint" in either the US or Great Britain.

Many thanks for your good wishes. Me being transient is posting this message from a Cancer Clinic.

Yes, I'm really as soft as a ripe banana!

LIfe is the journey and not the destination. My support is making it as pleasant as possible.

Sort of Good News. www.coursera.org is running the Univ Of Colorado's Power Electronics Series again(?) staring 25JAN16. I think it starts w/ the first of six courses which can lead to a Specialization Certificate. There is Tuition for the Certificate. But if you forgo such accolades, it is FREE. I think just "auditing" the first Course will be sufficient to satisfy my Curiosity. I have two higher-ed Degrees already. One person said to me: "If you get any more Degrees. You will become a Thermometer." As a Patent Atty, I rather give a witness the 3rd Degree, than receive anymore Degrees myself. So Check It Out. At the site Key-on: "power electronics"

USCDADNYC

Being an Autodidact I have at least 3 degrees of freedom! - XY and Z (Cartesian) or  theta, rho and phi (Spherical)