Power Supplies: Switching vs. Linear

Power Supplies: Switching vs. Linear

In this video we look at the design and differences between a switching and a linear power supply. We examine the pros and cons and look at which one is best for which application.

[learnelectronics]

Towards the beginning of the video, talking about power supply theory I mistakenly said the transformer converted the AC to DC. That is of course incorrect. Thanks to those who pointed out my mistake.

[teh]

I own both types but prefer the linear supply for radio transceivers. The linear supply will last forever with very few problems. The comparison was excellent, great video.

[TheRadiogeek]

Very nice job explaining this. You can get a very nice used name brand linear power supply with analog meters for about the same price as a new switcher. I have a nice 3A linear supply I got on EBay for $30. Nothing wrong with a switching power supply, I just like a power supply with a big transformer. Linear supplies are easier to repair too. Thanks for showing us the difference.

[georgechambers]

I too never really knew the difference between the two. Good to finally have it explained so succinctly. Thanks for another learning experience!

[autumnjeserich]

I scored an old hp linear supply for about 40 bucks from an estate sale. The thing might of been made in 1962 and is way to heavy to move around, its a beast of a power supply. Absolute game changer for repairing pcbs for me

[usersg]

I am not new to electronics but up to now I had always compared the linear- and switch-mode power supplies only from the weight, size, heat dissipation, and efficiency point of view. In all these considerations SMPS was always the winner. Somehow, the ripple aspect on the output DC just fell by the wayside. Thereby, actually, it should be very obvious to all.
Now, I will have to do more objective differentiation between the two types - depending upon the application. Thanks for a very nice video.

[AnotherMaker]

I know I'm late to the party on this one, Paul, but fantastic as always. I really appreciate the diagram and straight forward descriptions.

[michaelpadovani]

Great video describing the comparison between the two. Having the scope really provides a visual element to help the confused understand.

[keithcamcom]

Could you explain 'high frequency DC' it's HF AC until it goes through another transformer to be converted to the required voltage to be rectified back to DC is it not? please correct me if I'm wrong. (DC cannot be processed by a transformer)

[DouglasKryder]

the tekpower tp3005t is a ~$75US 30v 5a linear that is about 10lbs and 10"x 5"x 7.75"[it has a strong hand strap on top for easy carry] . when i was shopping i noticed these are popular with a lot of youtube phone/laptop repair content providers as well as diy electronic maker types. most of whom purchased the units. whenever i'm looking at units to buy i look at what is used by people who make their living repairing electronics as well as the diy & hobbyist segment. i've had the tp3005t for ~6 months and no problems yet. Paul, you mentioned 3 downsides to linear, weight, size, portability. this tp3005t matches a switching on all 3. you should see if tekpower would be interested in providing a test unit to appear in a future edition of switching vs linear review.

[ntag]

IMO linear is the way to go. I've had a lab setup since the 70s. A super clean linear supply will be something like 15v, 5a. Size of a rack mount CRT scope and weight of about 30lbs.

My recently purchased Dr Meter linear PS-305DM, 30v, 5a I'm using to get a dead battery pack, hopefully, back up and running. Most likely the Dr Meter is the same form factor as in this video. One of the cells was ultra low at 0.014v. I chose to charge at 15mA CC and voltage at 0.50V CV. Took about an hour for the CC indicator to go off and the CV indicator to light. Gradually increased the voltage and current as the battery became charged.

The linear might make a difference in very low output application as above and when powering very low power like devices like watches. The display reading did not suffer from any display jitter or bouncing digits during very low output.

I've worked many years in power supply manufacturing, a maker that specialized in supplies only. I have a preference for linear.

[gordselectronicshobby]

A good switching power supply that has a clean output as a linear would, costs a lot more than a linear power supply. I chose a linear power supply because it is a simpler design. Good job on the simplicity of your video.

[georgesiv]

Can you suggest a good model for starters? I am currently look to buy my first linear power supply for electronics projects and there is just so many to choose from.

[நக்மாசெல்]

Noise explanation is good. I like it. M

[davidbrewer]

It is all about noise....most things it does not matter so much but in very low signal level, high signal to noise ratio electronics or analogue instrumentation it makes a MASSIVE difference. In these applications, linear wins every time.

[oscarrodriguez-mklz]

Hello, today which would you recommend, the linear or the switched?

[andrewverran]

Great video, have you any information on removing the short circuit protection on a linear power supply or make it switchable on/off ?
Regards
Andrew

[standishgeezer]

Overall, a good video. When describing the linear circuit however (@ 2:50) you suggested that, on the secondary side of the transformer you get DC. This is, of course, not the case: the voltage is still AC (just stepped down) and does not become DC until it has been rectified. Just thought I should clarify for those new to the subject.

[Martin-otxj]

Hi there, i think for laptop repair mainboard and mobile mainboard Linear is much better than Switching !! because Linear has protection on it and its secure for people doesn't have so much experience about electronic but Switching doesn't protection on switch off the voltage !! what do you think about that ? thankyou .

[pinterelectric]

Wait, the xformer doesn’t convert ac to dc, the rectifier does