A memory module is formed on an integrated circuit by arranging memory cells in columns, and routing signal wires from module pins at an edge of the module to respective memory cells. The metal trace structure including a channel therein for the receipt of underfill. The control device determines whether the stored job requires user authentication. The stub is used to instantiate an object class. Wherein A, X, Y, R1 and R2 are as defined in the description. When more than one phase is used simultaneously to produce sufficient torque for the application, the increased leakage flux and the reduced permeability of parts of the magnetic circuit distort the information gleaned from diagnostic pulses.