I'm trying to get 12volt 1.5amps from my cars dirty 10~15 volt supply.
After a little Googling I'm guessing I'm going to be using the lm1085t.
I found two schematics on the data sheet but i'm wondering which one would be the best to use.
The first is this:
Obviously it has 4.75V in and 3.3V out, so what would I need to change to this to get 12V out? **broken link removed**
Secondly, there's this: **broken link removed**
I'm pretty certain that this is the one I need, but, I'm a little screwed on the math >> Vout = 1.25(1+ R2/R1) ??
.. and what type of Cap is C1?
Ah bugger. I completely overlooked that.
Although, I think I should be good there, I'm really only going to be using this while the car is running, plus I have dual 100amp batteries.
But, on the off chance that there's a better solution, what would you suggest?
Ah bugger. I completely overlooked that.
Although, I think I should be good there, I'm really only going to be using this while the car is running, plus I have dual 100amp batteries.
But, on the off chance that there's a better solution, what would you suggest?
As Eric noted, a linear regulator will not boost voltage, so it will obviously not work for voltages less then 12V plus the dropout voltage of the regulator. But normal battery voltage is 12.6V with the engine off, and >13V with the engine running, so it should work for normal battery conditions in a car.
Not sure why the OP wanted to go down to 10V which is essentially a dead battery(?).