Rdson-based current sensing system

A device includes a current mirror, a switch, first and second current paths, first and second buffers, a variable resistor, a temperature-sensing circuit, and a controller. The first current path is coupled between the current mirror's input and the switch. The switch switches between ground and a transistor based on a control signal. The second current path is coupled between a first current mirror output and ground. The first buffer is coupled to a second current mirror output. The second buffer is coupled to the variable resistor, which is coupled to the first buffer. The temperature-sensing circuit provides a device temperature to the controller, which is coupled to a first buffer output and determines a first adjustment to the first and second current paths and a second adjustment to the variable resistor based on the device temperature.