Voltage regulator options

[crankler]

which is the better/best option as voltage regulator: LDO regulator, 78xx regulator or switching regulator? i'm using it to power microcontroller, comparators, sensors, etc.

i'm only familiar with the 78xx regulator.. they say it's inefficient so is there a better yet simple option?

 

[KJ6EAD]

It depends on the situation. Do you want a separate unit or built in? What is the input and output voltage/frequency? How important is cost/size/weight? Are you running on batteries?

 

[ckshivaram]

what is the current rating.... LDO cannot operate at higher currents. LM seires can withstand 1A of current... there are metal capped regulatores ie power regulators that can withstand uptp 3A of current....

 

[cool.man]

Most of the boards/projects uses 78xx series,you can use them, it works well.
Switching regulators are more efficient than 78xx regulator but has a high cost than 78xx regulators.

 

[hitesh19872419]

78xx are good cheaper and easy to use but if you want a good switching regulator with line voltage regulation than you must go for lm2575 it will not be cheaper

 

[crankler]

Thanks for the replies...

Do you want a separate unit or built in?

i would use a built in regulator.

Are you running on batteries?

No. I would use a transformer connected to bridge cicuit and capacitor filter... then connected to the regulator.

what is the current rating

Probably, i would need a max. of 1mA

---------- Post added at 03:54 ---------- Previous post was at 03:30 ----------

LM2575-5 looks good but it needs an inductor which i'm sure i won't find any store around.

 

[Takeshi-san]

If you have sensitive sensors, remember, that switching regulator is a good source of EMI. I would recommend 78xx regulator

 

[smd_lover]

And for such small currents an LM2575 will not raise your energy-efficiency.
The transformer is relatively the biggest energy waister here.
If you want low energy consumption use a ECO transformer or an SMPS power supply.

 

[crankler]

maybe, i'll just stick with 78xx regulator... it's the most commonly-used and it's connections is very simple.

 

[Embedded_Geek]

By using switching regulator you can save energy. Whenever you design a circuit always try to save energy.

 

[cool.man]

By using switching regulator you can save energy. Whenever you design a circuit always try to save energy.

It is right that by using switching regulators you can save energy but it is expensive than 78xx.
I have used switching regulator and inductor was a little bit problem for me because the inductor i brought from the market didnt work and i made my own inductor.

 

[Tahmid]

Hi,
If you aren't running on batteries, I would say it's best to use 78xx as this is what's most used as regulators, is very cheap and very easy circuit.
However, if efficiency and battery life (if operated on battery) are key factors, then you would have to go to switching regulator.

Take a look at L4971. It is a switching regulator in DIP package.
Datasheet: http://www.datasheetcatalog.org/datasheet/stmicroelectronics/5598.pdf

Hope this helps.
Tahmid.