In this video author is comparing in practice a buck converter with LM7805 linear voltage regulator. Here is the showdown buck converter vs linear voltage regulator.
In the video:
- Why & when you should use Buck converters?
- Advantages of linear voltage regulators
- Disadvantages of linear voltage regulators
- How to use linear voltage regulator?
- Where is buck converter used?
- Availability of Buck converters.
- Nomenclature with voltage regulators,
- How to use buck converters?
- Comparison of their usage,
- Testing both under loads for long time,
- Drawbacks of buck converters
What you learn from the comparison:
- Linear voltage regulator (78xx) use a lot more voltage compared to buck converter.
- Linear voltage converter heats up a lot to dissipate extra current,
- It switches off after heating up, and switches back on again.
- It consumes a lot more power compared to buck converter,
- Buck converter can provide variable output (by varying the potentiometer), whereas, a linear voltage regulator is stuck at only 1 output.
There are 2 mistakes in the video:
- 5:02 – 5:08 – correct calculations should be: (12V – 5V) x 0.42A = 2.94W
- 5:17 – 5:23 – correct calculations should be: (12V – 5V) x 0.22A = 1.54W
Hi, buck converters are really cool, but they generate such amount of noise , my last project include 4 pots conected to 4 ADC ports and they could’t get stable , values are always floating 10 to 15% of real value. The only solution was power te circuit with an 7805 3Amps in TO3 case with an huge heatsink, stabilizating at 50ºC . My question is : isn’t there an efecience way to eliminate this noise ? Thank you
Rui Barroso there are many ways
1) Using a low ESR capacitor or connect parallel capacitances instead of one big one at the output ( tantalum caps have low ESR )
2) Linear regulators have better regulation and noise performance but aren’t efficient when then there is a lot of difference between vin and vout, so you have to use a combination of buck and linear regulator ( low dropout regulator :LDO).
3) check the range of current drawn from the supply and choose an LDO whose output is fairly constant over that range like less than 1%
The video is down, can someone reupload it?
Thank you, we have updated the video. Please refresh the page.
Good information for newcomers.
Thank You for your feedback.
Video is not here. Would be interested in seeing.
Hi Giselle Freude, the video is present on the page. Kindly refresh the page or check your browser flash settings.