voltage regulation doubts

Status
Not open for further replies.
C

chinnacreative88

Newbie level 2
Joined
Feb 19, 2010
Messages
2
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Location
india
Activity points
1,293
if my input is 4-5v can i get regulated output of 13.8v only by using lm317 regulator for battery charging .........If not for 13.8v output regulated voltage what should be the range of input voltage.
 

Yes, you can get 13.8V output.

But for adjustable voltage regulator like LM317 there is no way you can feed in 4-5V and expect 13.8V at output.

Minimum input voltage to ensure 13.8V output has to be 13.8 + 1.7(Voltage drop across LM317) = 15.5V

Hope this helps
 

Hi,
the min 15.5V is very optimistic calculated, mostly need an LM317 >+2-2.5V, but thes is really detail...
In ythes case you need a switched regulator_a "step-up" typ.
You can go to w"w.national.com, select power>> "webench" & you have a good possibility to select/design with SW he optimal "Simple Switch Family" with minimal components count + BOM to end...
K.
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…