how do you convert 9V to 3.6V

[Gizmotech]

how do you convert 9V to 3.6V using resistors and will it work? Any help appreciated. In ther words, how do I do the sums?

[sivan_and]

Whatz the required load curent...Whether regulation necessary..

[Gizmotech]

it's to run 3.6V LED from a 9V battery

[paulb]

http://www.allaboutcircuits.com/vol_1/chpt_6/1.html
Note that your load (whatever you need the 3.6V for) is one of the divider resistors. You need to know its resistance, or how much current it draws at 3.6V (R=V/I). If the load changes (draws more or less current), its voltage will also change. Using resistors only to drop voltage has no voltage regulation characteristic.

[sivan_and]

Many options:
Constant current source or Exotic LED drivers (white) from National.com or ti.com texas inst
Or simple current limitting resistor>>>>9-3.6/ LED current in milliamp = resistance in Kohms.
For 10ma LED Current R=540 OHMS (560 OHMS nearest commercial value)

[Shoog]

If all you are doing is lighting a few LEDs then use a simple series resistor to derive the correct current. The total voltage across the arrangement is totally unimportant, its the current that counts.

Shoog

[lgreen]

The LED equation is here.

Just use 1 resistor in series, use the formula.

For a typical amber LED Vf is about 2V, and If is about 20mA. So for 9V I get 350 ohms. To be safe, I'd use 500 or 1K. They get pretty bright even without using them to their max specs.