The HG809SM3/TR with SOT-23-3 package is a surface mount monitor and reset circuit device manufactured by HGSEMI. It is a low power device and is RoHS compliant, meaning it does not contain hazardous materials such as lead, mercury, cadmium, and more. This device can be used to provide early warning of system problems and reset the system under a failure condition. The operating voltage range is 2.7 V to 18.0 V DC and can provide power supply reset signals through an internal current limit circuit or an external resistive circuit. The reset output is open-drain type and the maximum operating temperature is 125 degrees Celsius.