wicus
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I'm busy designing my own christmas lights using the AT89S52. it works 100% using 32 LED's , one connected to each I/O port via a 220Ohm resistor. I need to expand ths now by adding 20 LED's to each port, but is struggling to calculate all resistor values to be able to use a transistor. What transistors can be used to switch a max of 2A on each IO Port from a 12V Supply, with 5V/oV from the I/O Ports ?
I'm really clueless should I use PNP or NPN transistors, and what values of resistors to use for a 12V supply, and the AT89S52 which switches out 5V
I've posted the schematic I'm using here
**broken link removed**
But now I need to add lots of LED's in parallel and add a transistor in each Leg
Any asistance will be mush appreciated
I'm really clueless should I use PNP or NPN transistors, and what values of resistors to use for a 12V supply, and the AT89S52 which switches out 5V
I've posted the schematic I'm using here
**broken link removed**
But now I need to add lots of LED's in parallel and add a transistor in each Leg
Any asistance will be mush appreciated