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What is the gain of a comparator?
A. The basic function of a high-gain comparator is to determine whether an input voltage is higher or lower than a reference voltage—and to present that decision as one of two voltage levels, established by the output’s limiting values.
What is meant by voltage comparator?
A voltage comparator is an electronic circuit that compares two input voltages and lets you know which of the two is greater. In this circuit, a positive voltage appears at the output if the input voltage is greater than the reference voltage; otherwise, no output voltage exists.
Do you need a pull up resistor for a comparator?
A lot of comparators just have an open-collector output and this is normally used by connecting a pull-up resistor to a positive supply rail. In your circuit you have shown a TL081 (written since the op edited it to an LM311) and this doesn’t qualify as a comparator – it’s an op-amp and as such, it doesn’t need a pull-up resistor.
What is the role of R1 at the output of this comparator?
What is the role of R1 at the output of this comparator? A lot of comparators just have an open-collector output and this is normally used by connecting a pull-up resistor to a positive supply rail.
How is a voltage comparator connected to a power supply?
Here, the open collector output from the voltage comparator is connected to a voltage source via a single pull-up resistor (and an LED for indication) which pulls the single output high to the power supply. When the output switch is HIGH it creates a high impedance path, therefore no current flows as V OUT = Vcc.
Can a resistive voltage divider be used as a comparator?
Generally, a resistive voltage divider is used to set the input reference voltage of a comparator, but a battery source, zener diode or potentiometer for a variable reference voltage can all be used as shown.