I have finished the x0x i was building and everything seems hunky dory except the LED's.
The brightness is normal on a few LED's but dim on most of them ; randomly.
This x0x was partially built when i got it , should i go through and double check the soldering is ok ? Resistor values too ?
Would it be a bad connection to ground that would cause this or bad connection to power ?
Any else have this problem ? Did you find a solution ?
x0x uneven LED brightness.
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Please be positive and constructive with your questions and comments.
- rv0
- Posts: 395
- Joined: Tue Jul 14, 2009 4:50 pm
Re: x0x uneven LED brightness.
definitely check the resistor values (you can visually inspect that..)
- cleaninglady
- Posts: 38
- Joined: Thu Jun 14, 2012 6:33 am
Re: x0x uneven LED brightness.
The values are as they should be. Are there any resistors that can be changed to affect the brightness of all resistors ?
- antto
- Posts: 1636
- Joined: Thu Apr 15, 2010 3:21 pm
Re: x0x uneven LED brightness.
sadly no.. each LED has a dedicated current limiting resistor
the brightness being different could be due to
- resistor tollerance
- LED tollerance (could there be some LEDs which look similar as the others but are not?)
- a combination of both
- something else
i got 40 red LEDs from the same bag with 10k 5% resistors in both my x0xes, and surely some of them are very slightly dimmer than most.. but it's not enough to annoy me
the brightness being different could be due to
- resistor tollerance
- LED tollerance (could there be some LEDs which look similar as the others but are not?)
- a combination of both
- something else
i got 40 red LEDs from the same bag with 10k 5% resistors in both my x0xes, and surely some of them are very slightly dimmer than most.. but it's not enough to annoy me
- cleaninglady
- Posts: 38
- Joined: Thu Jun 14, 2012 6:33 am
Re: x0x uneven LED brightness.
Thanks ! Yes , if this was for me i wouldn't care but i'm building it for someone else so unfortunately it's an issue.
I might swap some LED's positions and see the difference.
I might swap some LED's positions and see the difference.
- hamburgers
- Posts: 1058
- Joined: Wed Dec 21, 2005 8:25 pm
Re: x0x uneven LED brightness.
I have run into this and just replaced the LEDs until the brightness was suitable
- cleaninglady
- Posts: 38
- Joined: Thu Jun 14, 2012 6:33 am
Re: x0x uneven LED brightness.
Thanks mome rath !
Yes , i think the conclusion from a few sources (and may own attempts to fix it in other ways) was :
The x0xb0x circuit was originally designed for high brightness type LED's.
The x0xb0x i was servicing was built with normal brightness LED's, so no tinkering with parallel resistors or changing resistor values will actually fix the problem, changing your LED's to High Brightness seems the only solid solution.
Good to say it here i suppose, as it will be a good future reference for others.
Yes , i think the conclusion from a few sources (and may own attempts to fix it in other ways) was :
The x0xb0x circuit was originally designed for high brightness type LED's.
The x0xb0x i was servicing was built with normal brightness LED's, so no tinkering with parallel resistors or changing resistor values will actually fix the problem, changing your LED's to High Brightness seems the only solid solution.
Good to say it here i suppose, as it will be a good future reference for others.
Please be positive and constructive with your questions and comments.