The LM311DT is a low-power, single comparator IC manufactured by STMicroelectronics. It is designed for direct interfacing between digital logic systems and analog signals. The LM311DT is used to detect differences between the two levels of a voltage input, providing an output that switches from low to high when the voltage exceeds a certain threshold. It features a single open-drain output, adjustable hysteresis, and a wide supply voltage range, making it suitable for a variety of applications such as motor control, monitor switching, and audio equipment.