A method and a reference circuit for bias current switching are provided for implementing an integrated temperature sensor. A first bias current is generated and constantly applied to a thermal sensing diode. A second bias current is provided to the thermal sensing diode by selectively switching a multiplied current from a current multiplier to the thermal sensing diode or to a load diode. The reference circuit includes a reference current source coupled to current mirror. The current mirror provides a first bias current to a thermal sensing diode. The current mirror is coupled to a current multiplier that provides a multiplied current. A second bias current to the thermal sensing diode includes the first bias current and the multiplied current from the current multiplier. The second bias current to the thermal sensing diode is provided by selectively switching the multiplied current between the thermal sensing diode and a dummy load diode.