[TenTec] LED Dropping resister

Sinisa Hristov shristov at ptt.yu
Fri Dec 19 14:33:06 EST 2003


Marty Hartwell wrote:

>         If one wanted to play with LED's what is a good value for a dropping
> resister to use?


R = (Vsupply - Vled) / Iled

R       : resistor value
Vsupply : power supply voltage, must be > Vled
Vled    : voltage drop on LED, generally from 1.6 V to 2.7 V
Iled    : current, try 5 mA = 0.005 A

Example:
  Vsupply = 12 V
  Vled    =  2 V
  Iled    =  5 mA = 0.005 A
  R       = (12 - 2) / 0.005 = 2000 Ohms (use 1800 or 2200 Ohms)


73,

Sinisa  YT1NT, VA3TTN


More information about the TenTec mailing list