| 摘要 |
<p>PURPOSE:To stabilize actions by using the temperature dependency of the forward direction voltage of a junction diode provided in the integrated circuit of a cooling object part in an electronic device, detecting a junction temperature and stabilizing it at the most suitable value. CONSTITUTION:A cooling object part 1 discharges heat in the cooling object part by an operating cooling fan 2. When the rotational abnormality of the cooling fan is detected, a trouble discriminating circuit 6 gives a warning to a displaying part 10. When a temperature abnormality is detected by an exhaust gas temperature detector 3, the trouble discriminating circuit 6 reports the abnormality to the displaying part 10, executes a necessary refuge processing to accompany action stop and after that, cuts off a power source by a power source control circuit 9. A junction diode 14 is provided for an integrated circuit 13 in the cooling object part 1 and a constant current is always supplied to it by a constant current circuit 7 when it operates. The set junction temperature of the integrated circuit element is detected by the forward direction current of the junction diode 14, the rotation of the cooling fan 2 is controlled and the above-mentioned junction temperature is always held at a constant value.</p> |
