8301
Tangent Corner / Re: LED Electronics guys out there?
« on: April 13, 2010, 01:45:30 PM »
Hi Dave,
According to ohm's law E=I*R and this transposes to R=E/I.
If you have 23 LED's each requiring a current of 25mA then that's 23*25=575mA.
If the p.s.u voltage is 9.5 Volts then R=9.5/0.575 or 17 Ohms.
So if you connect all the LED's in series (observing the correct polarity, of course) with a 17 Ohm resistor that should do it.
The resistor wattage is calculated as W=V*A or W=9.5*0.575 then that's 6 Watts (it will get warm in operation).
Hope this helps,
Tweakie.
According to ohm's law E=I*R and this transposes to R=E/I.
If you have 23 LED's each requiring a current of 25mA then that's 23*25=575mA.
If the p.s.u voltage is 9.5 Volts then R=9.5/0.575 or 17 Ohms.
So if you connect all the LED's in series (observing the correct polarity, of course) with a 17 Ohm resistor that should do it.
The resistor wattage is calculated as W=V*A or W=9.5*0.575 then that's 6 Watts (it will get warm in operation).
Hope this helps,
Tweakie.