LED Control
Hello,
In the digital output section in the datasheet it says that those pins are not designed for draw static current. But:
- Could it control several LEDs (one LED per pin) with 1mA if the maximum is 2mA in Lowest Drive Strength Setting?
- If I level up the setting to Low or High, could it drive?
I am in a cost effective design and I need the minimum components.
Thanks.
Audio Signal Processors
hardware
led
adau1467
SigmaDSP Audio Processors
Hello JaviUrbano,
The drive strength settings have more to do with sudden changes with the edges of signals and they are not a current limit setting. If you do something similar to what we do in the design of the eval board you will need to use around a 475 ohm resistor to get the LED brightness usable. Doing the math, if the LED drops 2.0V, which is fairly common, then that leaves 1.3V to drop across the resistor. 1.3/475 will give you almost 3ma of current. You really should not drive that much current statically from the pin. We got this info for the datasheet from the designers. When the designers are worried about something that makes me worried.
We use a hex inverter on our eval board.
I have also used a pre-biased transistor to drive an LED. This is really low cost and small. The one I used is the DTC114YUA but there are others around.
Dave T
Hello DaveThib ,
Thank you for the quick answer, it was very clear.
Kind regards.
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