Patent ID: 7856108

Claim:
A method for preventing an output device from being damaged, said output device being set up to a system, and said system including a processor, and said method comprising the steps of: (a) said processor dividing output values of said output device into a plurality of areas; (b) defining a ratio for said each area, and said ratio values are arranged in an ascending order; (c) said processor receiving a desired output value; (d) said processor determining a mapping area where a converted maximum output value within a previous predetermined time is located from said areas; (e) determining a current area where said desired output value is located from said areas; and (f) determining whether or not said ratio value of said current area is larger than said ratio value of said mapping area; if yes, then said processor will use a substantially non-distorted ratio value to calculate said desired output value to obtain a first actual output volume, and said output device will output said first actual output volume, wherein said substantially non-distorted ratio value is larger than said ratio value of said current area, and said mapping area having said substantially non-distorted area is situated adjacent to said current area; if no, then said processor will calculate said desired output value and said ratio value of said current area to obtain a second actual output volume, and said output device will output said second actual output volume, wherein said second actual output volume is lower than said maximum output volume permitted by said output device to prevent said output device from being damaged.