Apparatus and method for detecting the temperature in a disk memory device

A disk memory device, comprising:

• a CPU for controlling operations in the device;
• a spindle motor (SPM) for rotating at least one disk medium having a plurality of data tracks;
• a head mechanism for holding a read/write head on the data recording tracks of the at least one disk medium;
• a voice coil motor (VCM) for driving the head mechanism by angular rotation;
• a head control circuit for providing read/write control signals to the head from the CPU;
• and
• a temperature detecting circuit for detecting environmental temperature in the device for deciding an appropriate condition for providing the read/write control signals to the head;
• the temperature detecting circuit, comprising:
• a first voltage source dividing circuit connected to a voltage source in series, the first voltage source dividing circuit includes a first and a second elements having temperature-independent resistances;
• a second voltage source dividing circuit connected to the voltage source in series, the second voltage source dividing circuit includes a third element having temperature-independent resistance and a temperature detecting element having temperature-dependent resistance;
• an analog-to-digital converter for reading a digital value of a first electric potential at a first connecting point between the first and the second elements in the first voltage source dividing circuit and a second electric potential at a second connecting point between the third element and the temperature detecting element in the second voltage source dividing circuit
• a calculation mechanism for calculating an electric potential ratio using the digital values detected by the ADC based on the first and the second electric potentials;
• and
• an electric potential ratio/temperature converting mechanism for acquiring a temperature that corresponds to the electric potential ratio by referencing to a predetermined electric potential ratio-temperature characteristic.

A method for detecting temperature in an equipment that comprises a CPU for controlling operations in the equipment, a first voltage source dividing circuit including a first pair of elements connected to a voltage source in series, the first pair of elements includes a first and a second temperature-independent resistances;

• a second voltage source dividing circuit including a second pair of elements connected to voltage source in series, the second pair of elements includes a third element of temperature-independent resistance and a temperature detecting element of temperature-dependent resistance, comprising:
• reading a first electric potential at a first connecting point positioned between the first and the second elements in the first voltage source dividing circuit and a second electric potential at a second connecting point positioned between the third element and the temperature detecting element in the second voltage source dividing circuit;
• converting the first and the second electric potentials into respective digital values;
• calculating an electric potential ratio between the first electric potential and the second electric potential by using the converted digital values;
• and
• acquiring a temperature in response to the calculated electric potential ratio by referencing to a predetermined electric potential ratio-temperature characteristic.