resistors for LEDs question
#1
5 speed
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resistors for LEDs question
i have previosly played around with a couple of LEDs from radio shack and the bulbs are 3.7volts min and 4.5 volts max and i did the equation that Illusion had on his website:thumbup:, and he recomended 470-Ohm resistors and i got the ½ watt ones and used them and they came out fine
i went to radio shack yesterday and i saw that they had 470-Ohm ¼ watt ones so i picked up both
so my question is do i use the ¼ watt ones or the ½ watt ones
Thank you,
RY2K
here is a picture, it's hard to read so i drew on the pic
i want to do this the correct way, and not mess up my car so i apreciate any input
i went to radio shack yesterday and i saw that they had 470-Ohm ¼ watt ones so i picked up both
so my question is do i use the ¼ watt ones or the ½ watt ones
Thank you,
RY2K
here is a picture, it's hard to read so i drew on the pic
i want to do this the correct way, and not mess up my car so i apreciate any input
#2
wattage is a measurement of power. the wattage rating on a resistor is basically how many watts/milliwats it can safely dissipate as heat. i'd go with the 1/2 watt ones. better to be safe than sorry.
#4
I usually use 220 ohm.....but da jus me.
If anything is to get screwed up by using the wrong resistor, it would be the LED itself and nothing else....feel free to correct me if im wrong
If anything is to get screwed up by using the wrong resistor, it would be the LED itself and nothing else....feel free to correct me if im wrong
#6
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Originally posted by /^Blackmagik^\
wattage is a measurement of power. the wattage rating on a resistor is basically how many watts/milliwats it can safely dissipate as heat. i'd go with the 1/2 watt ones. better to be safe than sorry.
wattage is a measurement of power. the wattage rating on a resistor is basically how many watts/milliwats it can safely dissipate as heat. i'd go with the 1/2 watt ones. better to be safe than sorry.
Originally posted by JERZY-STYLZ
I usually use 220 ohm.....but da jus me.
I usually use 220 ohm.....but da jus me.
If anything is to get screwed up by using the wrong resistor, it would be the LED itself and nothing else....feel free to correct me if im wrong
Originally posted by /^Blackmagik^\
Ohm's law E=I/R :dunno:
Ohm's law E=I/R :dunno:
check out the web page it's explained really well
http://www.igd4u.com/modules.php?op=...=article&sid=2
#7
Originally posted by RY2K
E = I*R so R = E/I
check out the web page it's explained really well
http://www.igd4u.com/modules.php?op=...=article&sid=2
E = I*R so R = E/I
check out the web page it's explained really well
http://www.igd4u.com/modules.php?op=...=article&sid=2
:doh: i knew that.... it's been a while since i used it though
here's the extended equation to calculate power in a circuit.
using W=E^2/R you'll see that the 1/4 watt resistors won't cut it. and a burning resistor don't smell good at all.
#8
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Originally posted by /^Blackmagik^\
:doh: i knew that.... it's been a while since i used it though
here's the extended equation to calculate power in a circuit.
using W=E^2/R you'll see that the 1/4 watt resistors won't cut it. and a burning resistor don't smell good at all.
:doh: i knew that.... it's been a while since i used it though
here's the extended equation to calculate power in a circuit.
using W=E^2/R you'll see that the 1/4 watt resistors won't cut it. and a burning resistor don't smell good at all.
my car smells like cucumber melon, and a burnt resistor would not be very :grinpimp:
#9
Originally posted by RY2K
thanks for the equation picture
my car smells like cucumber melon, and a burnt resistor would not be very :grinpimp:
thanks for the equation picture
my car smells like cucumber melon, and a burnt resistor would not be very :grinpimp: