I need to know what the circuit on the Backlight ON pin looks like on the BitsyXb.
Documentation indicates that it is an open collector that can switch voltages up to 30V. It would be good to know what it's current sink capability is.
What I am finding is that there seems to be an additional impedance to ground on that pin of approximately 1.2K. Is there a resistor to ground on that pin or maybe a transient supression device with an impedance of 1.2K?
What this does is affectively creates a voltage divider and makes it difficult/impossible to pull the pin up to the rail through another resistor. Please advise Thanks