What is a Pull-up Resistor?A pull-up resistor is used in electronic logic circuits to ensure a known state for a signal. It is usually used in combination with transistors and switches to ensure the voltage between ground and Vcc is actively controlled when the switch is open (similar to a pull-down resistor).It is not a special kind of resistor, it is a normally fixed value resistor connected between a supply voltage and input pin.This can sound confusing at first, so let’s go into an example.D