| 摘要 |
<p>PURPOSE:To detect an abnormality by providing an oscillating means whose oscillation frequency is varied in accordance with a variation of a temperature and obtaining a temperature monitoring signal by comparing the oscillation frequency of the oscillating means and the reference frequency. CONSTITUTION:An LSI 1 is provided with an RC oscillator 3 connected to an external capacitor 2, a reference value register 11 for inputting reference count value data 9 from the outside and a comparator 14 for comparating a count value of a counter 5 and a count set value 13, etc. Subsequently, when the LSI 1 becomes an abnormal high temperature, a resistance value of the circuit 3 becomes high, and an oscillation wave number becomes low. Also, at the time point when an abnormal sampling signal 17 is outputted by a fall of a gate signal 8, a difference between the count value 12 and the count value 13 becomes >=3, therefore, a comparing signal 15 becomes a logical value '1', and an abnormality signal 19 is informed to an external device from a flip-flop 18. Accordingly, an abnormal temperature in the device can be detected.</p> |
