Hi,
I am looking at this eval board which supposedly works and I am wondering how the LED circuit operates. It seems to me that the U537 inverter will not go to a low state which turns on the LED. The output of U526 is an open drain output which gets pulled up to 1.8V thru a 10K resistor. Won't that mean that the input to U537 will be 1.8V max? The U537 is operating at 3.3V which has a Vih = 2.0V (min) and Vil = .8V max.
Thanks!
I am looking at this eval board which supposedly works and I am wondering how the LED circuit operates. It seems to me that the U537 inverter will not go to a low state which turns on the LED. The output of U526 is an open drain output which gets pulled up to 1.8V thru a 10K resistor. Won't that mean that the input to U537 will be 1.8V max? The U537 is operating at 3.3V which has a Vih = 2.0V (min) and Vil = .8V max.
Thanks!