The "MAX809LEUR+T" is a low dropout (LDO) regulator from Analog Devices. This regulator provides fixed and adjustable output voltage options and delivers up to 500mA of continuous current. It has an exceptionally low quiescent current of just 1µA and a very low dropout voltage of just 0.5V at 500mA. The device is designed to operate over a wide input voltage range of up to 20V and uses current-limit and thermal-shutdown protection features to ensure safe operation. It also features a very low output noise of just 25µV RMS. The device is available in a SOT-223 package and is rated for operation over ambient temperatures from -40°C to +125°C. This makes the device ideal for applications such as cellular phones, portable data access devices, laptops, and PDAs.