Open collector means that there is nothing connected internally to the collector of the output transistor. This means that the circuit can sink current (pull current to GND) but cannot be a source of current.1. What is meant by open collector output?
Since there is no source of current the output pin never goes above 0V. For this to happen, you have to provide a voltage source via a pullup resistor to some positive voltage.2. What is the relationship between pull-up resistors and open collector output of a particular IC?
You don't want the resistor to be too low otherwise you will exceed the current sink capabilities of the output transistor and the output voltage will rise too far above 0V.3. Are there limitations when we choosing resistor values for pullup resistors ?
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by Duane Benson
by Duane Benson
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