Driving a group of leds with a buffer?

Community Projects
1

Hello all!

I am having 32 input signals that come from an ADUM2400 (isolated buffer) and these signals go as inputs to 32 pins of an FPGA development board.

What I would like is to have 32 LEDs in the middle for debuggind reasons but looking at the ADUM 2400 datasheet (without being sure) I saw that the maximum output current per channel is less than 1mA, so not enough. I thought that having 4 8bit buffers would do the job. I found the 74LVC245APW from NXP but I cannot find inside the datasheet if they are able to drive with enough current (10mA per LED) each channel.

Does anybody have any idea if this buffer would do the job?

Thank you in advance!

2

http://www.nxp.com/documents/data_sheet … CH245A.pdf

Table 4

spec: Io

When designing for modern devices I use high efficiency LEDs that will light a 1mA or less. Like these:

http://rohmfs.rohm.com/en/products/data … _p-eco.pdf

This help with the total power consumption and heat of the circuits plus needs much less demand on a power supply.

3

Thanks for the answer!

Actually the LEDs are for debuggin reasons so I dont care if the light intensity is not that big. So I do not need to drive them with 10mA. I will drive them with up to 3mA. I have tested that and it is visible. So I will use the 74LV245A from TI that can drive up to 8mA per channel.

Regards