Interfacing LED's with 18F4520

[paddy_p]

Hello,

I have to interface around 120 LED's to PIC18F4520.

I am planning to do it with Latch IC 74HCT574. But it increases number of latch IC's.

As per the datasheet the maximum current sourced and sunk by all ports of micro controller is 200mA. Is it enough to drive all the LED's?

Please suggest.

Thanks,
paddy

 

[internetuser2k12]

to drive leds use uln2003A with your 74hct574.

 

[paddy_p]

Okay. I will use.

But i am looking for any other alternative to do the same.

By this way i have to use 15 numbers of Latch and ULN2003 IC's.

 

[internetuser2k12]

Yes. That's right

 

[paddy_p]

Yes. That's right

As per the datasheet the maximum current sourced and sunk by all ports of micro controller is 200mA.

And for 120 LED's i need around 2.5A current. So what i need to do in this case.

thanks

 

[internetuser2k12]

I said to use uln2003 between your 74HCT574 and leds. Connect mcu and 74hct574 and uln i/p to o/p of 74hct574 and leds to uln2003 o/p.

 

[wp100]

Hi,

Using a 4514/15 will give you 16 outputs per chip and a ULN2803 will give you 8 lines instead of the 2003 7 lines.

 

[internetuser2k12]

You can use that also.