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large 5x7 dot matrix display grid help

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4rvm

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Hi, I would like to model a "billboard" for a display on a train layout. This display would be a grid of 60 ltp747r 5x7 common cathode matrices that would be driven from a pic 16f877. The display would be arranged as 12 5x7 chips across by 5 chips down. My initial question is a confirmation of what kind of power would be needed at a 20% duty cycle given a 13ma datasheet normal brightness level at 100% per led. I am trying to figure out what to drive the rows and columns with, especially the rows where I'm not finding too high a rating on what I think are needed pchannel mosfets (hexfets). Any initial advice on this project is much appreciated! Thanks.
 

AtilaPap

New Member
Will this help?

In datasheet you can find leds data and and with little math you will find out.
Power transistor will do the job but it must be fast.
 
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