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Electronics => Electronics => Topic started by: airman00 on July 23, 2008, 05:37:11 AM

Title: LED Matrix Tutorial
Post by: airman00 on July 23, 2008, 05:37:11 AM

http://www.instructables.com/id/LED-matrix-using-shift-registers/?ALLSTEPS (http://www.instructables.com/id/LED-matrix-using-shift-registers/?ALLSTEPS)

(http://www.instructables.com/files/deriv/FQP/VQXF/FHAVXW8U/FQPVQXFFHAVXW8U.MEDIUM.jpg)
(http://www.instructables.com/files/deriv/FF0/6U1X/FHEJ12BU/FF06U1XFHEJ12BU.MEDIUM.jpg)

Title: Re: LED Matrix Tutorial
Post by: izua on July 23, 2008, 05:44:09 AM

ouch, shift registers can't supply a lot of current XD

Title: Re: LED Matrix Tutorial
Post by: airman00 on July 23, 2008, 05:55:36 AM

what do you mean?

enough current for what application? For a matrix of LEDs they are fine , but anything else they are probably not enough.

Title: Re: LED Matrix Tutorial
Post by: izua on July 23, 2008, 06:19:18 AM

they say +-10mA (source/sink) in the datasheet i have. maybe some other 74XX spec will have a different power rating.
However, notice the dim lights in the second picture ^^

Title: Re: LED Matrix Tutorial
Post by: airman00 on July 23, 2008, 08:52:58 AM

Quote from: izua on July 23, 2008, 06:19:18 AM

they say +-10mA (source/sink) in the datasheet i have. maybe some other 74XX spec will have a different power rating.
However, notice the dim lights in the second picture ^^

they are dim because they are running at 1/8 duty cycle . Read the link I posted for more info. If you want them brighter just run them at 7/8 duty cycle or something like that , lol .