Termpro Audio Forum Post New Topic  Post A Reply
my profile | directory login | register | faq | forum home

  next oldest topic   next newest topic
» Termpro Audio Forum » Installer's Corner » Advanced Topics » LED's and Resistors

- UBBFriend: Email this page to someone!    
Author Topic: LED's and Resistors
Big Truck
New Member
Member # 13478

Icon 1 posted      Profile for Big Truck   Author's Homepage   Email Big Truck   Send New Private Message       Edit/Delete Post   Reply With Quote 
Does anyone know where i could find out how much resistance to put inline with a LED?
Posts: 9 | From: UT | Registered: Sep 2003  |  IP: Logged | Report this post to a Moderator
MTX_TECH
Member
Member # 12184

Icon 1 posted      Profile for MTX_TECH     Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Big Truck:
Does anyone know where i could find out how much resistance to put inline with a LED?
Try this website out.

http://www.7volts.com/led_resistor.htm
Posts: 141 | From: here | Registered: Mar 2003  |  IP: Logged | Report this post to a Moderator
emu
Senior Member
Member # 1832

Icon 1 posted      Profile for emu   Email emu   Send New Private Message       Edit/Delete Post   Reply With Quote 
That's great except the graph is for 12V regulated. Use the lowest value resistor for 12V on 14.4V and it'll fry fairly quickly.

Generally, for a car, anything around 700 ohms is fine. 680 and 750 are the closest standards. This is for a red or green LED. Blue LED's require more of a voltage drop so a resistor around 560 ohms is used.
Posts: 768 | From: Ottawa, On, Canada | Registered: May 2000  |  IP: Logged | Report this post to a Moderator
oldtimer
Senior Member
Member # 2073

Icon 1 posted      Profile for oldtimer   Author's Homepage   Email oldtimer   Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Big Truck:
Does anyone know where i could find out how much resistance to put inline with a LED?
Use Ohm's law. The resistor acts Like a current regulator. a typical LED drops about 1.7 to 2 volts or so. so the resistor drops about 10 volts on a 12 volt supply. on a 24 volt supply it would be 22 volts ,etc. so V/I=R

so 10 volts/.02 amps = 500 ohms

22 volts/.02 amps = 1100 ohms

The current comes from the LED's Rating.

The lower the resistor value the brighter the LED Runs.

--------------------
My 45's want fit in that slot!
Posts: 1147 | From: Rowlett, TX, USA | Registered: Jun 2000  |  IP: Logged | Report this post to a Moderator
   

Quick Reply
Message:

HTML is not enabled.
UBB Code™ is enabled.

Instant Graemlins
   


Post New Topic  Post A Reply Close Topic   Feature Topic   Move Topic   Delete Topic next oldest topic   next newest topic
- Printer-friendly view of this topic
Hop To:


(c) 1996-2007 WHE Inc, Carson City Nevada, USA

Powered by Infopop Corporation
UBB.classic™ 6.7.2