Vibration apparatus for a mobile telecommunication terminal and method for controlling the same

A vibration device for generating a vibration in a mobile terminal, comprising:

• a vibrator for generating vibration at a predetermined vibration frequency, the predetermined vibration frequency determined according to a resonance point of the mobile terminal;
• a controller for controlling the vibrator;
• and
• a memory for storing a plurality of predetermined vibration frequencies determined in consideration of possible changes in the resonance point of the mobile terminal,
• wherein the controller varies the vibration frequency between the predetermined vibration frequencies.

A vibration apparatus for generating a vibration in a mobile terminal, comprising:

• a vibrator for generating vibration;
• a frequency generator for generating a driving signal having a predetermined frequency, the predetermined frequency determined according to a resonance point of the mobile terminal;
• a driver for driving the vibrator according to the driving signal provided from the frequency generator;
• a vibration measurer for measuring the vibration generated by the vibrator;
• and
• a frequency controller for determining a frequency of the driving signal according to the measured vibration and for changing to another predetermined vibration frequency from among a plurality of predetermined vibration frequencies determined in consideration of possible changes in the resonance point of the mobile terminal.

A method for controlling a vibration apparatus for generating a vibration in a mobile terminal, comprising the steps of:

• periodically changing at successive time periods a frequency of a driving signal within a first frequency range, the first frequency range determined by a resonance point of the mobile terminal;
• generating vibration according to the driving signal having the periodically changed frequency, and then measuring vibration values each time period;
• comparing the measured vibration values each time period and selecting a frequency indicating a maximum vibration value within the first frequency range;
• and
• setting the selected frequency as a frequency of the driving signal.

A method for controlling a vibration apparatus for generating a vibration in a mobile terminal, comprising the steps of:

• a) periodically changing a frequency of a driving signal within a first frequency range at successive time periods, the first frequency range determined according to a resonance point of the mobile terminal;
• b) generating vibration according to the driving signal having the periodically changed frequency, and then measuring vibration values each time period;
• c) comparing the measured vibration values each time period and selecting a frequency indicating a maximum vibration value within the first frequency range;
• and
• d) periodically changing a frequency of the driving signal with a second frequency range centered on the selected frequency.