Apparatus and method for controlling a stepping motor

Method for controlling the rotating speed of a stepping motor configured to carry a scanning head of a scanner, said method comprising:

• mapping a plurality of sets of electrical-parameter means to different ranges of rotating speed of said stepping motor to form a mapping table, each of said plurality of sets of electrical-parameter means being selectively coupled to said stepping motor, when a specified resolution of said scanner relating to a specified range of rotating speed of said stepping motor being determined on an application interface, said application interface selects a set of electrical-parameter means of said plurality of sets of electrical-parameter means according to said mapping table, said plurality of sets of electrical-parameter means being used to eliminate the back EMF (Electro-Mechanical Force) in said stepping motor within different resolutions of said scanner;
• and
• connecting a power source to a selected set of electrical-parameter means of said plurality sets of electrical-parameter means according to said mapping table, said driving means connected to said selected set of electrical-parameter means being used to provide the power that is suitable for the operation of said stepping motor without the back EMF, said set of selected electrical-parameter means of said plurality sets of electrical-parameter means enabling said stepping motor to rotate within said specified range of rotating speed without the back EMF, said specified range of rotating speed enabling said scanner having said specified resolution.

A method of simultaneously controlling the speed and back EMF of a stepping motor in an image scanner, the stepping motor configured to move a scanning head of the image scanner at a plurality of stepping motor speeds, the method comprising:

• creating a mapping table which maps a user-selected scanning resolution onto a corresponding one of a plurality of stepping motor speeds;
• selecting a scanning resolution;
• outputing a signal indicating a selected one of a plurality of sets of electrical parameter means which must be connected to the motor to produce a stepping motor speed corresponding to said selected scanning resolution;
• activating at least one switch in response to said signal to thereby selectively connect a power source to said stepping motor via said selected set of electrical parameter means to both control the speed at which the stepping motor moves the scanning head in accordance with the selected scanning resolution, and also to mitigate the back EMF of said motor, said selected set of electrical parameter means comprising at least two electrical components.