Abstract: A method selects a group of values for an external impedance used to configure a semiconductor. The external impedance has a tolerance and the group of values include a quantity. The method includes providing a measurement circuit as a portion of the semiconductor; determining tolerances associated with the measurement circuit; selecting one of the external impedance tolerance and the quantity of the group of values; computing the other of the external impedance tolerance and the quantity of the group of values, as a function of the measurement circuit tolerances and the selected one of the external impedance tolerance and the quantity of the group of values; and selecting discrete values for the group of values of the external impedance as a function of the computing.