A comparator circuit of a temperature sensor includes an output node and a variable current node. The output node is a first voltage at a given temperature when a current at the variable current node is less than a threshold current, and a different second voltage at the given temperature when the current at the variable current node is more than the threshold current. A variable resistance circuit includes at least n resistors of different resistive values connected in series between the variable current node of the comparator and a supply voltage, where n is an integer of 4 or more. A switching circuit is provided to selectively bypasses individual ones of the n resistors during a test sequence to determine a trip temperature of the sensor.