Q: DCI used as current limiters?

G

Gordon

Guest
All,

Conscious original intent of DCI: Our application involves driving 76
discrete LEDs using a XC3S50. For cost reasons, we've decided to
drive each LED statically (as opposed to scanning). Each IO is
operating at LVDCI_33.

Can we use DCI to current limit (~430 ohm) the LEDs? It looks like
LVDCI_33 is driver impedance controlled only, so the 3S50 will be a
current source. VCCO is 3.3V.

Any comments / experience is appreciated.

Gordon
 
Gordon,

Sure, this will work.

Just remember that the power is then dissipated internally in the IO
transistors.

Austin

Gordon wrote:
All,

Conscious original intent of DCI: Our application involves driving 76
discrete LEDs using a XC3S50. For cost reasons, we've decided to
drive each LED statically (as opposed to scanning). Each IO is
operating at LVDCI_33.

Can we use DCI to current limit (~430 ohm) the LEDs? It looks like
LVDCI_33 is driver impedance controlled only, so the 3S50 will be a
current source. VCCO is 3.3V.

Any comments / experience is appreciated.

Gordon
Click to expand...
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top