The comparator In electronics, a comparator is a device which compares two voltage (less current) and returns a digital signal indicating which one is bigger. Elements of this type are often used in electronics, for example, to check if the input signal has a certain value. If input, the signal from the sensor a value of the comparator can act as a control system element. When you connect to one of the inputs of the comparator the signal from termoopornika, and the other reference voltage to obtain a simple thermostat. It is sufficient that the output plug control relay heater.
A comparator circuit compares two voltage at the input, the output is testimony to the high (supply voltage) or low (voltage supply), or a negative voltage in the case of a symmetrical security element. In most cases, the comparator is implemented using a special chip. It strengthens the difference between the input voltages. Strengthening the system is very high, so even with a slight difference in output will be provided. If the input voltage nieodwracającym more, the output voltage will be high position, but if a larger voltage occurs at the input converts the output of the system will be low.
With notes on high gain in the circuit of the comparator this element is extremely vulnerable to noise and interference at the input of the system. At a time when the difference between the input signals is less than the voltage międzyszczytowe noise present in the input signal, it may cause oscillation of the output signal is a rapid change of state from high to low and back. In practice this is very problematic. Therefore, to improve this circuit to make it more resistant to noise, adds a feedback loop that provides the system with hysteresis operation.
Comparators have a wide range of applications in electronic systems. In addition to their application in systems of control and management, for example, to stabilize the physical parameters such as temperature, engine speed, or brightness, they are used in power supply systems, class D amplifiers (comparator is a simple system designed for modulating (PWM) element Converter analog-to-digital , or even as a generator, with the addition of the RC system. Thanks to feedback from komparatorem the system can work stable, being extremely resistant to noise and interference in the input signals.